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nvme.c revision 1.39
      1 /*	$NetBSD: nvme.c,v 1.39 2018/04/18 10:11:45 nonaka Exp $	*/
      2 /*	$OpenBSD: nvme.c,v 1.49 2016/04/18 05:59:50 dlg Exp $ */
      3 
      4 /*
      5  * Copyright (c) 2014 David Gwynne <dlg (at) openbsd.org>
      6  *
      7  * Permission to use, copy, modify, and distribute this software for any
      8  * purpose with or without fee is hereby granted, provided that the above
      9  * copyright notice and this permission notice appear in all copies.
     10  *
     11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
     12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
     13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
     14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
     15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
     16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
     17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
     18  */
     19 
     20 #include <sys/cdefs.h>
     21 __KERNEL_RCSID(0, "$NetBSD: nvme.c,v 1.39 2018/04/18 10:11:45 nonaka Exp $");
     22 
     23 #include <sys/param.h>
     24 #include <sys/systm.h>
     25 #include <sys/kernel.h>
     26 #include <sys/atomic.h>
     27 #include <sys/bus.h>
     28 #include <sys/buf.h>
     29 #include <sys/conf.h>
     30 #include <sys/device.h>
     31 #include <sys/kmem.h>
     32 #include <sys/once.h>
     33 #include <sys/proc.h>
     34 #include <sys/queue.h>
     35 #include <sys/mutex.h>
     36 
     37 #include <uvm/uvm_extern.h>
     38 
     39 #include <dev/ic/nvmereg.h>
     40 #include <dev/ic/nvmevar.h>
     41 #include <dev/ic/nvmeio.h>
     42 
     43 #include "ioconf.h"
     44 
     45 #define	B4_CHK_RDY_DELAY_MS	2300	/* workaround controller bug */
     46 
     47 int nvme_adminq_size = 32;
     48 int nvme_ioq_size = 1024;
     49 
     50 static int	nvme_print(void *, const char *);
     51 
     52 static int	nvme_ready(struct nvme_softc *, uint32_t);
     53 static int	nvme_enable(struct nvme_softc *, u_int);
     54 static int	nvme_disable(struct nvme_softc *);
     55 static int	nvme_shutdown(struct nvme_softc *);
     56 
     57 #ifdef NVME_DEBUG
     58 static void	nvme_dumpregs(struct nvme_softc *);
     59 #endif
     60 static int	nvme_identify(struct nvme_softc *, u_int);
     61 static void	nvme_fill_identify(struct nvme_queue *, struct nvme_ccb *,
     62 		    void *);
     63 
     64 static int	nvme_ccbs_alloc(struct nvme_queue *, uint16_t);
     65 static void	nvme_ccbs_free(struct nvme_queue *);
     66 
     67 static struct nvme_ccb *
     68 		nvme_ccb_get(struct nvme_queue *, bool);
     69 static void	nvme_ccb_put(struct nvme_queue *, struct nvme_ccb *);
     70 
     71 static int	nvme_poll(struct nvme_softc *, struct nvme_queue *,
     72 		    struct nvme_ccb *, void (*)(struct nvme_queue *,
     73 		    struct nvme_ccb *, void *), int);
     74 static void	nvme_poll_fill(struct nvme_queue *, struct nvme_ccb *, void *);
     75 static void	nvme_poll_done(struct nvme_queue *, struct nvme_ccb *,
     76 		    struct nvme_cqe *);
     77 static void	nvme_sqe_fill(struct nvme_queue *, struct nvme_ccb *, void *);
     78 static void	nvme_empty_done(struct nvme_queue *, struct nvme_ccb *,
     79 		    struct nvme_cqe *);
     80 
     81 static struct nvme_queue *
     82 		nvme_q_alloc(struct nvme_softc *, uint16_t, u_int, u_int);
     83 static int	nvme_q_create(struct nvme_softc *, struct nvme_queue *);
     84 static int	nvme_q_delete(struct nvme_softc *, struct nvme_queue *);
     85 static void	nvme_q_submit(struct nvme_softc *, struct nvme_queue *,
     86 		    struct nvme_ccb *, void (*)(struct nvme_queue *,
     87 		    struct nvme_ccb *, void *));
     88 static int	nvme_q_complete(struct nvme_softc *, struct nvme_queue *q);
     89 static void	nvme_q_free(struct nvme_softc *, struct nvme_queue *);
     90 static void	nvme_q_wait_complete(struct nvme_softc *, struct nvme_queue *,
     91 		    bool (*)(void *), void *);
     92 
     93 static struct nvme_dmamem *
     94 		nvme_dmamem_alloc(struct nvme_softc *, size_t);
     95 static void	nvme_dmamem_free(struct nvme_softc *, struct nvme_dmamem *);
     96 static void	nvme_dmamem_sync(struct nvme_softc *, struct nvme_dmamem *,
     97 		    int);
     98 
     99 static void	nvme_ns_io_fill(struct nvme_queue *, struct nvme_ccb *,
    100 		    void *);
    101 static void	nvme_ns_io_done(struct nvme_queue *, struct nvme_ccb *,
    102 		    struct nvme_cqe *);
    103 static void	nvme_ns_sync_fill(struct nvme_queue *, struct nvme_ccb *,
    104 		    void *);
    105 static void	nvme_ns_sync_done(struct nvme_queue *, struct nvme_ccb *,
    106 		    struct nvme_cqe *);
    107 static void	nvme_getcache_fill(struct nvme_queue *, struct nvme_ccb *,
    108 		    void *);
    109 static void	nvme_getcache_done(struct nvme_queue *, struct nvme_ccb *,
    110 		    struct nvme_cqe *);
    111 
    112 static void	nvme_pt_fill(struct nvme_queue *, struct nvme_ccb *,
    113 		    void *);
    114 static void	nvme_pt_done(struct nvme_queue *, struct nvme_ccb *,
    115 		    struct nvme_cqe *);
    116 static int	nvme_command_passthrough(struct nvme_softc *,
    117 		    struct nvme_pt_command *, uint16_t, struct lwp *, bool);
    118 
    119 static int	nvme_get_number_of_queues(struct nvme_softc *, u_int *);
    120 
    121 #define NVME_TIMO_QOP		5	/* queue create and delete timeout */
    122 #define NVME_TIMO_IDENT		10	/* probe identify timeout */
    123 #define NVME_TIMO_PT		-1	/* passthrough cmd timeout */
    124 #define NVME_TIMO_SY		60	/* sync cache timeout */
    125 
    126 #define nvme_read4(_s, _r) \
    127 	bus_space_read_4((_s)->sc_iot, (_s)->sc_ioh, (_r))
    128 #define nvme_write4(_s, _r, _v) \
    129 	bus_space_write_4((_s)->sc_iot, (_s)->sc_ioh, (_r), (_v))
    130 /*
    131  * Some controllers, at least Apple NVMe, always require split
    132  * transfers, so don't use bus_space_{read,write}_8() on LP64.
    133  */
    134 static inline uint64_t
    135 nvme_read8(struct nvme_softc *sc, bus_size_t r)
    136 {
    137 	uint64_t v;
    138 	uint32_t *a = (uint32_t *)&v;
    139 
    140 #if _BYTE_ORDER == _LITTLE_ENDIAN
    141 	a[0] = nvme_read4(sc, r);
    142 	a[1] = nvme_read4(sc, r + 4);
    143 #else /* _BYTE_ORDER == _LITTLE_ENDIAN */
    144 	a[1] = nvme_read4(sc, r);
    145 	a[0] = nvme_read4(sc, r + 4);
    146 #endif
    147 
    148 	return v;
    149 }
    150 
    151 static inline void
    152 nvme_write8(struct nvme_softc *sc, bus_size_t r, uint64_t v)
    153 {
    154 	uint32_t *a = (uint32_t *)&v;
    155 
    156 #if _BYTE_ORDER == _LITTLE_ENDIAN
    157 	nvme_write4(sc, r, a[0]);
    158 	nvme_write4(sc, r + 4, a[1]);
    159 #else /* _BYTE_ORDER == _LITTLE_ENDIAN */
    160 	nvme_write4(sc, r, a[1]);
    161 	nvme_write4(sc, r + 4, a[0]);
    162 #endif
    163 }
    164 #define nvme_barrier(_s, _r, _l, _f) \
    165 	bus_space_barrier((_s)->sc_iot, (_s)->sc_ioh, (_r), (_l), (_f))
    166 
    167 #ifdef NVME_DEBUG
    168 static __used void
    169 nvme_dumpregs(struct nvme_softc *sc)
    170 {
    171 	uint64_t r8;
    172 	uint32_t r4;
    173 
    174 #define	DEVNAME(_sc) device_xname((_sc)->sc_dev)
    175 	r8 = nvme_read8(sc, NVME_CAP);
    176 	printf("%s: cap  0x%016"PRIx64"\n", DEVNAME(sc), nvme_read8(sc, NVME_CAP));
    177 	printf("%s:  mpsmax %u (%u)\n", DEVNAME(sc),
    178 	    (u_int)NVME_CAP_MPSMAX(r8), (1 << NVME_CAP_MPSMAX(r8)));
    179 	printf("%s:  mpsmin %u (%u)\n", DEVNAME(sc),
    180 	    (u_int)NVME_CAP_MPSMIN(r8), (1 << NVME_CAP_MPSMIN(r8)));
    181 	printf("%s:  css %"PRIu64"\n", DEVNAME(sc), NVME_CAP_CSS(r8));
    182 	printf("%s:  nssrs %"PRIu64"\n", DEVNAME(sc), NVME_CAP_NSSRS(r8));
    183 	printf("%s:  dstrd %"PRIu64"\n", DEVNAME(sc), NVME_CAP_DSTRD(r8));
    184 	printf("%s:  to %"PRIu64" msec\n", DEVNAME(sc), NVME_CAP_TO(r8));
    185 	printf("%s:  ams %"PRIu64"\n", DEVNAME(sc), NVME_CAP_AMS(r8));
    186 	printf("%s:  cqr %"PRIu64"\n", DEVNAME(sc), NVME_CAP_CQR(r8));
    187 	printf("%s:  mqes %"PRIu64"\n", DEVNAME(sc), NVME_CAP_MQES(r8));
    188 
    189 	printf("%s: vs   0x%04x\n", DEVNAME(sc), nvme_read4(sc, NVME_VS));
    190 
    191 	r4 = nvme_read4(sc, NVME_CC);
    192 	printf("%s: cc   0x%04x\n", DEVNAME(sc), r4);
    193 	printf("%s:  iocqes %u (%u)\n", DEVNAME(sc), NVME_CC_IOCQES_R(r4),
    194 	    (1 << NVME_CC_IOCQES_R(r4)));
    195 	printf("%s:  iosqes %u (%u)\n", DEVNAME(sc), NVME_CC_IOSQES_R(r4),
    196 	    (1 << NVME_CC_IOSQES_R(r4)));
    197 	printf("%s:  shn %u\n", DEVNAME(sc), NVME_CC_SHN_R(r4));
    198 	printf("%s:  ams %u\n", DEVNAME(sc), NVME_CC_AMS_R(r4));
    199 	printf("%s:  mps %u (%u)\n", DEVNAME(sc), NVME_CC_MPS_R(r4),
    200 	    (1 << NVME_CC_MPS_R(r4)));
    201 	printf("%s:  css %u\n", DEVNAME(sc), NVME_CC_CSS_R(r4));
    202 	printf("%s:  en %u\n", DEVNAME(sc), ISSET(r4, NVME_CC_EN) ? 1 : 0);
    203 
    204 	r4 = nvme_read4(sc, NVME_CSTS);
    205 	printf("%s: csts 0x%08x\n", DEVNAME(sc), r4);
    206 	printf("%s:  rdy %u\n", DEVNAME(sc), r4 & NVME_CSTS_RDY);
    207 	printf("%s:  cfs %u\n", DEVNAME(sc), r4 & NVME_CSTS_CFS);
    208 	printf("%s:  shst %x\n", DEVNAME(sc), r4 & NVME_CSTS_SHST_MASK);
    209 
    210 	r4 = nvme_read4(sc, NVME_AQA);
    211 	printf("%s: aqa  0x%08x\n", DEVNAME(sc), r4);
    212 	printf("%s:  acqs %u\n", DEVNAME(sc), NVME_AQA_ACQS_R(r4));
    213 	printf("%s:  asqs %u\n", DEVNAME(sc), NVME_AQA_ASQS_R(r4));
    214 
    215 	printf("%s: asq  0x%016"PRIx64"\n", DEVNAME(sc), nvme_read8(sc, NVME_ASQ));
    216 	printf("%s: acq  0x%016"PRIx64"\n", DEVNAME(sc), nvme_read8(sc, NVME_ACQ));
    217 #undef	DEVNAME
    218 }
    219 #endif	/* NVME_DEBUG */
    220 
    221 static int
    222 nvme_ready(struct nvme_softc *sc, uint32_t rdy)
    223 {
    224 	u_int i = 0;
    225 
    226 	while ((nvme_read4(sc, NVME_CSTS) & NVME_CSTS_RDY) != rdy) {
    227 		if (i++ > sc->sc_rdy_to)
    228 			return ENXIO;
    229 
    230 		delay(1000);
    231 		nvme_barrier(sc, NVME_CSTS, 4, BUS_SPACE_BARRIER_READ);
    232 	}
    233 
    234 	return 0;
    235 }
    236 
    237 static int
    238 nvme_enable(struct nvme_softc *sc, u_int mps)
    239 {
    240 	uint32_t cc, csts;
    241 	int error;
    242 
    243 	cc = nvme_read4(sc, NVME_CC);
    244 	csts = nvme_read4(sc, NVME_CSTS);
    245 
    246 	/*
    247 	 * See note in nvme_disable. Short circuit if we're already enabled.
    248 	 */
    249 	if (ISSET(cc, NVME_CC_EN)) {
    250 		if (ISSET(csts, NVME_CSTS_RDY))
    251 			return 0;
    252 
    253 		goto waitready;
    254 	} else {
    255 		/* EN == 0 already wait for RDY == 0 or fail */
    256 		error = nvme_ready(sc, 0);
    257 		if (error)
    258 			return error;
    259 	}
    260 
    261 	nvme_write8(sc, NVME_ASQ, NVME_DMA_DVA(sc->sc_admin_q->q_sq_dmamem));
    262 	nvme_barrier(sc, 0, sc->sc_ios, BUS_SPACE_BARRIER_WRITE);
    263 	delay(5000);
    264 	nvme_write8(sc, NVME_ACQ, NVME_DMA_DVA(sc->sc_admin_q->q_cq_dmamem));
    265 	nvme_barrier(sc, 0, sc->sc_ios, BUS_SPACE_BARRIER_WRITE);
    266 	delay(5000);
    267 
    268 	nvme_write4(sc, NVME_AQA, NVME_AQA_ACQS(sc->sc_admin_q->q_entries) |
    269 	    NVME_AQA_ASQS(sc->sc_admin_q->q_entries));
    270 	nvme_barrier(sc, 0, sc->sc_ios, BUS_SPACE_BARRIER_WRITE);
    271 	delay(5000);
    272 
    273 	CLR(cc, NVME_CC_IOCQES_MASK | NVME_CC_IOSQES_MASK | NVME_CC_SHN_MASK |
    274 	    NVME_CC_AMS_MASK | NVME_CC_MPS_MASK | NVME_CC_CSS_MASK);
    275 	SET(cc, NVME_CC_IOSQES(ffs(64) - 1) | NVME_CC_IOCQES(ffs(16) - 1));
    276 	SET(cc, NVME_CC_SHN(NVME_CC_SHN_NONE));
    277 	SET(cc, NVME_CC_CSS(NVME_CC_CSS_NVM));
    278 	SET(cc, NVME_CC_AMS(NVME_CC_AMS_RR));
    279 	SET(cc, NVME_CC_MPS(mps));
    280 	SET(cc, NVME_CC_EN);
    281 
    282 	nvme_write4(sc, NVME_CC, cc);
    283 	nvme_barrier(sc, 0, sc->sc_ios,
    284 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
    285 
    286     waitready:
    287 	return nvme_ready(sc, NVME_CSTS_RDY);
    288 }
    289 
    290 static int
    291 nvme_disable(struct nvme_softc *sc)
    292 {
    293 	uint32_t cc, csts;
    294 	int error;
    295 
    296 	cc = nvme_read4(sc, NVME_CC);
    297 	csts = nvme_read4(sc, NVME_CSTS);
    298 
    299 	/*
    300 	 * Per 3.1.5 in NVME 1.3 spec, transitioning CC.EN from 0 to 1
    301 	 * when CSTS.RDY is 1 or transitioning CC.EN from 1 to 0 when
    302 	 * CSTS.RDY is 0 "has undefined results" So make sure that CSTS.RDY
    303 	 * isn't the desired value. Short circuit if we're already disabled.
    304 	 */
    305 	if (ISSET(cc, NVME_CC_EN)) {
    306 		if (!ISSET(csts, NVME_CSTS_RDY)) {
    307 			/* EN == 1, wait for RDY == 1 or fail */
    308 			error = nvme_ready(sc, NVME_CSTS_RDY);
    309 			if (error)
    310 				return error;
    311 		}
    312 	} else {
    313 		/* EN == 0 already wait for RDY == 0 */
    314 		if (!ISSET(csts, NVME_CSTS_RDY))
    315 			return 0;
    316 
    317 		goto waitready;
    318 	}
    319 
    320 	CLR(cc, NVME_CC_EN);
    321 	nvme_write4(sc, NVME_CC, cc);
    322 	nvme_barrier(sc, 0, sc->sc_ios, BUS_SPACE_BARRIER_READ);
    323 
    324 	/*
    325 	 * Some drives have issues with accessing the mmio after we disable,
    326 	 * so delay for a bit after we write the bit to cope with these issues.
    327 	 */
    328 	if (ISSET(sc->sc_quirks, NVME_QUIRK_DELAY_B4_CHK_RDY))
    329 		delay(B4_CHK_RDY_DELAY_MS);
    330 
    331     waitready:
    332 	return nvme_ready(sc, 0);
    333 }
    334 
    335 int
    336 nvme_attach(struct nvme_softc *sc)
    337 {
    338 	uint64_t cap;
    339 	uint32_t reg;
    340 	u_int dstrd;
    341 	u_int mps = PAGE_SHIFT;
    342 	u_int ioq_allocated;
    343 	uint16_t adminq_entries = nvme_adminq_size;
    344 	uint16_t ioq_entries = nvme_ioq_size;
    345 	int i;
    346 
    347 	reg = nvme_read4(sc, NVME_VS);
    348 	if (reg == 0xffffffff) {
    349 		aprint_error_dev(sc->sc_dev, "invalid mapping\n");
    350 		return 1;
    351 	}
    352 
    353 	if (NVME_VS_TER(reg) == 0)
    354 		aprint_normal_dev(sc->sc_dev, "NVMe %d.%d\n", NVME_VS_MJR(reg),
    355 		    NVME_VS_MNR(reg));
    356 	else
    357 		aprint_normal_dev(sc->sc_dev, "NVMe %d.%d.%d\n", NVME_VS_MJR(reg),
    358 		    NVME_VS_MNR(reg), NVME_VS_TER(reg));
    359 
    360 	cap = nvme_read8(sc, NVME_CAP);
    361 	dstrd = NVME_CAP_DSTRD(cap);
    362 	if (NVME_CAP_MPSMIN(cap) > PAGE_SHIFT) {
    363 		aprint_error_dev(sc->sc_dev, "NVMe minimum page size %u "
    364 		    "is greater than CPU page size %u\n",
    365 		    1 << NVME_CAP_MPSMIN(cap), 1 << PAGE_SHIFT);
    366 		return 1;
    367 	}
    368 	if (NVME_CAP_MPSMAX(cap) < mps)
    369 		mps = NVME_CAP_MPSMAX(cap);
    370 	if (ioq_entries > NVME_CAP_MQES(cap))
    371 		ioq_entries = NVME_CAP_MQES(cap);
    372 
    373 	/* set initial values to be used for admin queue during probe */
    374 	sc->sc_rdy_to = NVME_CAP_TO(cap);
    375 	sc->sc_mps = 1 << mps;
    376 	sc->sc_mdts = MAXPHYS;
    377 	sc->sc_max_sgl = 2;
    378 
    379 	if (nvme_disable(sc) != 0) {
    380 		aprint_error_dev(sc->sc_dev, "unable to disable controller\n");
    381 		return 1;
    382 	}
    383 
    384 	sc->sc_admin_q = nvme_q_alloc(sc, NVME_ADMIN_Q, adminq_entries, dstrd);
    385 	if (sc->sc_admin_q == NULL) {
    386 		aprint_error_dev(sc->sc_dev,
    387 		    "unable to allocate admin queue\n");
    388 		return 1;
    389 	}
    390 	if (sc->sc_intr_establish(sc, NVME_ADMIN_Q, sc->sc_admin_q))
    391 		goto free_admin_q;
    392 
    393 	if (nvme_enable(sc, mps) != 0) {
    394 		aprint_error_dev(sc->sc_dev, "unable to enable controller\n");
    395 		goto disestablish_admin_q;
    396 	}
    397 
    398 	if (nvme_identify(sc, NVME_CAP_MPSMIN(cap)) != 0) {
    399 		aprint_error_dev(sc->sc_dev, "unable to identify controller\n");
    400 		goto disable;
    401 	}
    402 
    403 	/* we know how big things are now */
    404 	sc->sc_max_sgl = sc->sc_mdts / sc->sc_mps;
    405 
    406 	/* reallocate ccbs of admin queue with new max sgl. */
    407 	nvme_ccbs_free(sc->sc_admin_q);
    408 	nvme_ccbs_alloc(sc->sc_admin_q, sc->sc_admin_q->q_entries);
    409 
    410 	if (sc->sc_use_mq) {
    411 		/* Limit the number of queues to the number allocated in HW */
    412 		if (nvme_get_number_of_queues(sc, &ioq_allocated) != 0) {
    413 			aprint_error_dev(sc->sc_dev,
    414 			    "unable to get number of queues\n");
    415 			goto disable;
    416 		}
    417 		if (sc->sc_nq > ioq_allocated)
    418 			sc->sc_nq = ioq_allocated;
    419 	}
    420 
    421 	sc->sc_q = kmem_zalloc(sizeof(*sc->sc_q) * sc->sc_nq, KM_SLEEP);
    422 	for (i = 0; i < sc->sc_nq; i++) {
    423 		sc->sc_q[i] = nvme_q_alloc(sc, i + 1, ioq_entries, dstrd);
    424 		if (sc->sc_q[i] == NULL) {
    425 			aprint_error_dev(sc->sc_dev,
    426 			    "unable to allocate io queue\n");
    427 			goto free_q;
    428 		}
    429 		if (nvme_q_create(sc, sc->sc_q[i]) != 0) {
    430 			aprint_error_dev(sc->sc_dev,
    431 			    "unable to create io queue\n");
    432 			nvme_q_free(sc, sc->sc_q[i]);
    433 			goto free_q;
    434 		}
    435 	}
    436 
    437 	if (!sc->sc_use_mq)
    438 		nvme_write4(sc, NVME_INTMC, 1);
    439 
    440 	/* probe subdevices */
    441 	sc->sc_namespaces = kmem_zalloc(sizeof(*sc->sc_namespaces) * sc->sc_nn,
    442 	    KM_SLEEP);
    443 	nvme_rescan(sc->sc_dev, "nvme", &i);
    444 
    445 	return 0;
    446 
    447 free_q:
    448 	while (--i >= 0) {
    449 		nvme_q_delete(sc, sc->sc_q[i]);
    450 		nvme_q_free(sc, sc->sc_q[i]);
    451 	}
    452 disable:
    453 	nvme_disable(sc);
    454 disestablish_admin_q:
    455 	sc->sc_intr_disestablish(sc, NVME_ADMIN_Q);
    456 free_admin_q:
    457 	nvme_q_free(sc, sc->sc_admin_q);
    458 
    459 	return 1;
    460 }
    461 
    462 int
    463 nvme_rescan(device_t self, const char *attr, const int *flags)
    464 {
    465 	struct nvme_softc *sc = device_private(self);
    466 	struct nvme_attach_args naa;
    467 	uint64_t cap;
    468 	int ioq_entries = nvme_ioq_size;
    469 	int i;
    470 
    471 	cap = nvme_read8(sc, NVME_CAP);
    472 	if (ioq_entries > NVME_CAP_MQES(cap))
    473 		ioq_entries = NVME_CAP_MQES(cap);
    474 
    475 	for (i = 0; i < sc->sc_nn; i++) {
    476 		if (sc->sc_namespaces[i].dev)
    477 			continue;
    478 		memset(&naa, 0, sizeof(naa));
    479 		naa.naa_nsid = i + 1;
    480 		naa.naa_qentries = (ioq_entries - 1) * sc->sc_nq;
    481 		naa.naa_maxphys = sc->sc_mdts;
    482 		sc->sc_namespaces[i].dev = config_found(sc->sc_dev, &naa,
    483 		    nvme_print);
    484 	}
    485 	return 0;
    486 }
    487 
    488 static int
    489 nvme_print(void *aux, const char *pnp)
    490 {
    491 	struct nvme_attach_args *naa = aux;
    492 
    493 	if (pnp)
    494 		aprint_normal("at %s", pnp);
    495 
    496 	if (naa->naa_nsid > 0)
    497 		aprint_normal(" nsid %d", naa->naa_nsid);
    498 
    499 	return UNCONF;
    500 }
    501 
    502 int
    503 nvme_detach(struct nvme_softc *sc, int flags)
    504 {
    505 	int i, error;
    506 
    507 	error = config_detach_children(sc->sc_dev, flags);
    508 	if (error)
    509 		return error;
    510 
    511 	error = nvme_shutdown(sc);
    512 	if (error)
    513 		return error;
    514 
    515 	/* from now on we are committed to detach, following will never fail */
    516 	for (i = 0; i < sc->sc_nq; i++)
    517 		nvme_q_free(sc, sc->sc_q[i]);
    518 	kmem_free(sc->sc_q, sizeof(*sc->sc_q) * sc->sc_nq);
    519 	nvme_q_free(sc, sc->sc_admin_q);
    520 
    521 	return 0;
    522 }
    523 
    524 static int
    525 nvme_shutdown(struct nvme_softc *sc)
    526 {
    527 	uint32_t cc, csts;
    528 	bool disabled = false;
    529 	int i;
    530 
    531 	if (!sc->sc_use_mq)
    532 		nvme_write4(sc, NVME_INTMS, 1);
    533 
    534 	for (i = 0; i < sc->sc_nq; i++) {
    535 		if (nvme_q_delete(sc, sc->sc_q[i]) != 0) {
    536 			aprint_error_dev(sc->sc_dev,
    537 			    "unable to delete io queue %d, disabling\n", i + 1);
    538 			disabled = true;
    539 		}
    540 	}
    541 	sc->sc_intr_disestablish(sc, NVME_ADMIN_Q);
    542 	if (disabled)
    543 		goto disable;
    544 
    545 	cc = nvme_read4(sc, NVME_CC);
    546 	CLR(cc, NVME_CC_SHN_MASK);
    547 	SET(cc, NVME_CC_SHN(NVME_CC_SHN_NORMAL));
    548 	nvme_write4(sc, NVME_CC, cc);
    549 
    550 	for (i = 0; i < 4000; i++) {
    551 		nvme_barrier(sc, 0, sc->sc_ios,
    552 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
    553 		csts = nvme_read4(sc, NVME_CSTS);
    554 		if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_DONE)
    555 			return 0;
    556 
    557 		delay(1000);
    558 	}
    559 
    560 	aprint_error_dev(sc->sc_dev, "unable to shudown, disabling\n");
    561 
    562 disable:
    563 	nvme_disable(sc);
    564 	return 0;
    565 }
    566 
    567 void
    568 nvme_childdet(device_t self, device_t child)
    569 {
    570 	struct nvme_softc *sc = device_private(self);
    571 	int i;
    572 
    573 	for (i = 0; i < sc->sc_nn; i++) {
    574 		if (sc->sc_namespaces[i].dev == child) {
    575 			/* Already freed ns->ident. */
    576 			sc->sc_namespaces[i].dev = NULL;
    577 			break;
    578 		}
    579 	}
    580 }
    581 
    582 int
    583 nvme_ns_identify(struct nvme_softc *sc, uint16_t nsid)
    584 {
    585 	struct nvme_sqe sqe;
    586 	struct nvm_identify_namespace *identify;
    587 	struct nvme_dmamem *mem;
    588 	struct nvme_ccb *ccb;
    589 	struct nvme_namespace *ns;
    590 	int rv;
    591 
    592 	KASSERT(nsid > 0);
    593 
    594 	ccb = nvme_ccb_get(sc->sc_admin_q, false);
    595 	KASSERT(ccb != NULL); /* it's a bug if we don't have spare ccb here */
    596 
    597 	mem = nvme_dmamem_alloc(sc, sizeof(*identify));
    598 	if (mem == NULL) {
    599 		nvme_ccb_put(sc->sc_admin_q, ccb);
    600 		return ENOMEM;
    601 	}
    602 
    603 	memset(&sqe, 0, sizeof(sqe));
    604 	sqe.opcode = NVM_ADMIN_IDENTIFY;
    605 	htolem32(&sqe.nsid, nsid);
    606 	htolem64(&sqe.entry.prp[0], NVME_DMA_DVA(mem));
    607 	htolem32(&sqe.cdw10, 0);
    608 
    609 	ccb->ccb_done = nvme_empty_done;
    610 	ccb->ccb_cookie = &sqe;
    611 
    612 	nvme_dmamem_sync(sc, mem, BUS_DMASYNC_PREREAD);
    613 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_sqe_fill, NVME_TIMO_IDENT);
    614 	nvme_dmamem_sync(sc, mem, BUS_DMASYNC_POSTREAD);
    615 
    616 	nvme_ccb_put(sc->sc_admin_q, ccb);
    617 
    618 	if (rv != 0) {
    619 		rv = EIO;
    620 		goto done;
    621 	}
    622 
    623 	/* commit */
    624 
    625 	identify = kmem_zalloc(sizeof(*identify), KM_SLEEP);
    626 	*identify = *((volatile struct nvm_identify_namespace *)NVME_DMA_KVA(mem));
    627 
    628 	/* Convert data to host endian */
    629 	nvme_identify_namespace_swapbytes(identify);
    630 
    631 	ns = nvme_ns_get(sc, nsid);
    632 	KASSERT(ns);
    633 	KASSERT(ns->ident == NULL);
    634 	ns->ident = identify;
    635 
    636 done:
    637 	nvme_dmamem_free(sc, mem);
    638 
    639 	return rv;
    640 }
    641 
    642 int
    643 nvme_ns_dobio(struct nvme_softc *sc, uint16_t nsid, void *cookie,
    644     struct buf *bp, void *data, size_t datasize,
    645     int secsize, daddr_t blkno, int flags, nvme_nnc_done nnc_done)
    646 {
    647 	struct nvme_queue *q = nvme_get_q(sc);
    648 	struct nvme_ccb *ccb;
    649 	bus_dmamap_t dmap;
    650 	int i, error;
    651 
    652 	ccb = nvme_ccb_get(q, false);
    653 	if (ccb == NULL)
    654 		return EAGAIN;
    655 
    656 	ccb->ccb_done = nvme_ns_io_done;
    657 	ccb->ccb_cookie = cookie;
    658 
    659 	/* namespace context */
    660 	ccb->nnc_nsid = nsid;
    661 	ccb->nnc_flags = flags;
    662 	ccb->nnc_buf = bp;
    663 	ccb->nnc_datasize = datasize;
    664 	ccb->nnc_secsize = secsize;
    665 	ccb->nnc_blkno = blkno;
    666 	ccb->nnc_done = nnc_done;
    667 
    668 	dmap = ccb->ccb_dmamap;
    669 	error = bus_dmamap_load(sc->sc_dmat, dmap, data,
    670 	    datasize, NULL,
    671 	    (ISSET(flags, NVME_NS_CTX_F_POLL) ?
    672 	      BUS_DMA_NOWAIT : BUS_DMA_WAITOK) |
    673 	    (ISSET(flags, NVME_NS_CTX_F_READ) ?
    674 	      BUS_DMA_READ : BUS_DMA_WRITE));
    675 	if (error) {
    676 		nvme_ccb_put(q, ccb);
    677 		return error;
    678 	}
    679 
    680 	bus_dmamap_sync(sc->sc_dmat, dmap, 0, dmap->dm_mapsize,
    681 	    ISSET(flags, NVME_NS_CTX_F_READ) ?
    682 	    BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
    683 
    684 	if (dmap->dm_nsegs > 2) {
    685 		for (i = 1; i < dmap->dm_nsegs; i++) {
    686 			htolem64(&ccb->ccb_prpl[i - 1],
    687 			    dmap->dm_segs[i].ds_addr);
    688 		}
    689 		bus_dmamap_sync(sc->sc_dmat,
    690 		    NVME_DMA_MAP(q->q_ccb_prpls),
    691 		    ccb->ccb_prpl_off,
    692 		    sizeof(*ccb->ccb_prpl) * (dmap->dm_nsegs - 1),
    693 		    BUS_DMASYNC_PREWRITE);
    694 	}
    695 
    696 	if (ISSET(flags, NVME_NS_CTX_F_POLL)) {
    697 		if (nvme_poll(sc, q, ccb, nvme_ns_io_fill, NVME_TIMO_PT) != 0)
    698 			return EIO;
    699 		return 0;
    700 	}
    701 
    702 	nvme_q_submit(sc, q, ccb, nvme_ns_io_fill);
    703 	return 0;
    704 }
    705 
    706 static void
    707 nvme_ns_io_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
    708 {
    709 	struct nvme_sqe_io *sqe = slot;
    710 	bus_dmamap_t dmap = ccb->ccb_dmamap;
    711 
    712 	sqe->opcode = ISSET(ccb->nnc_flags, NVME_NS_CTX_F_READ) ?
    713 	    NVM_CMD_READ : NVM_CMD_WRITE;
    714 	htolem32(&sqe->nsid, ccb->nnc_nsid);
    715 
    716 	htolem64(&sqe->entry.prp[0], dmap->dm_segs[0].ds_addr);
    717 	switch (dmap->dm_nsegs) {
    718 	case 1:
    719 		break;
    720 	case 2:
    721 		htolem64(&sqe->entry.prp[1], dmap->dm_segs[1].ds_addr);
    722 		break;
    723 	default:
    724 		/* the prp list is already set up and synced */
    725 		htolem64(&sqe->entry.prp[1], ccb->ccb_prpl_dva);
    726 		break;
    727 	}
    728 
    729 	htolem64(&sqe->slba, ccb->nnc_blkno);
    730 
    731 	if (ISSET(ccb->nnc_flags, NVME_NS_CTX_F_FUA))
    732 		htolem16(&sqe->ioflags, NVM_SQE_IO_FUA);
    733 
    734 	/* guaranteed by upper layers, but check just in case */
    735 	KASSERT((ccb->nnc_datasize % ccb->nnc_secsize) == 0);
    736 	htolem16(&sqe->nlb, (ccb->nnc_datasize / ccb->nnc_secsize) - 1);
    737 }
    738 
    739 static void
    740 nvme_ns_io_done(struct nvme_queue *q, struct nvme_ccb *ccb,
    741     struct nvme_cqe *cqe)
    742 {
    743 	struct nvme_softc *sc = q->q_sc;
    744 	bus_dmamap_t dmap = ccb->ccb_dmamap;
    745 	void *nnc_cookie = ccb->ccb_cookie;
    746 	nvme_nnc_done nnc_done = ccb->nnc_done;
    747 	struct buf *bp = ccb->nnc_buf;
    748 
    749 	if (dmap->dm_nsegs > 2) {
    750 		bus_dmamap_sync(sc->sc_dmat,
    751 		    NVME_DMA_MAP(q->q_ccb_prpls),
    752 		    ccb->ccb_prpl_off,
    753 		    sizeof(*ccb->ccb_prpl) * (dmap->dm_nsegs - 1),
    754 		    BUS_DMASYNC_POSTWRITE);
    755 	}
    756 
    757 	bus_dmamap_sync(sc->sc_dmat, dmap, 0, dmap->dm_mapsize,
    758 	    ISSET(ccb->nnc_flags, NVME_NS_CTX_F_READ) ?
    759 	    BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
    760 
    761 	bus_dmamap_unload(sc->sc_dmat, dmap);
    762 	nvme_ccb_put(q, ccb);
    763 
    764 	nnc_done(nnc_cookie, bp, lemtoh16(&cqe->flags), lemtoh32(&cqe->cdw0));
    765 }
    766 
    767 /*
    768  * If there is no volatile write cache, it makes no sense to issue
    769  * flush commands or query for the status.
    770  */
    771 static bool
    772 nvme_has_volatile_write_cache(struct nvme_softc *sc)
    773 {
    774 	/* sc_identify is filled during attachment */
    775 	return  ((sc->sc_identify.vwc & NVME_ID_CTRLR_VWC_PRESENT) != 0);
    776 }
    777 
    778 static bool
    779 nvme_ns_sync_finished(void *cookie)
    780 {
    781 	int *result = cookie;
    782 
    783 	return (*result != 0);
    784 }
    785 
    786 int
    787 nvme_ns_sync(struct nvme_softc *sc, uint16_t nsid, int flags)
    788 {
    789 	struct nvme_queue *q = nvme_get_q(sc);
    790 	struct nvme_ccb *ccb;
    791 	int result = 0;
    792 
    793 	if (!nvme_has_volatile_write_cache(sc)) {
    794 		/* cache not present, no value in trying to flush it */
    795 		return 0;
    796 	}
    797 
    798 	ccb = nvme_ccb_get(q, true);
    799 	if (ccb == NULL)
    800 		return EAGAIN;
    801 
    802 	ccb->ccb_done = nvme_ns_sync_done;
    803 	ccb->ccb_cookie = &result;
    804 
    805 	/* namespace context */
    806 	ccb->nnc_nsid = nsid;
    807 	ccb->nnc_flags = flags;
    808 	ccb->nnc_done = NULL;
    809 
    810 	if (ISSET(flags, NVME_NS_CTX_F_POLL)) {
    811 		if (nvme_poll(sc, q, ccb, nvme_ns_sync_fill, NVME_TIMO_SY) != 0)
    812 			return EIO;
    813 		return 0;
    814 	}
    815 
    816 	nvme_q_submit(sc, q, ccb, nvme_ns_sync_fill);
    817 
    818 	/* wait for completion */
    819 	nvme_q_wait_complete(sc, q, nvme_ns_sync_finished, &result);
    820 	KASSERT(result != 0);
    821 
    822 	return (result > 0) ? 0 : EIO;
    823 }
    824 
    825 static void
    826 nvme_ns_sync_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
    827 {
    828 	struct nvme_sqe *sqe = slot;
    829 
    830 	sqe->opcode = NVM_CMD_FLUSH;
    831 	htolem32(&sqe->nsid, ccb->nnc_nsid);
    832 }
    833 
    834 static void
    835 nvme_ns_sync_done(struct nvme_queue *q, struct nvme_ccb *ccb,
    836     struct nvme_cqe *cqe)
    837 {
    838 	int *result = ccb->ccb_cookie;
    839 	uint16_t status = NVME_CQE_SC(lemtoh16(&cqe->flags));
    840 
    841 	if (status == NVME_CQE_SC_SUCCESS)
    842 		*result = 1;
    843 	else
    844 		*result = -1;
    845 
    846 	nvme_ccb_put(q, ccb);
    847 }
    848 
    849 static bool
    850 nvme_getcache_finished(void *xc)
    851 {
    852 	int *addr = xc;
    853 
    854 	return (*addr != 0);
    855 }
    856 
    857 /*
    858  * Get status of volatile write cache. Always asynchronous.
    859  */
    860 int
    861 nvme_admin_getcache(struct nvme_softc *sc, int *addr)
    862 {
    863 	struct nvme_ccb *ccb;
    864 	struct nvme_queue *q = sc->sc_admin_q;
    865 	int result = 0, error;
    866 
    867 	if (!nvme_has_volatile_write_cache(sc)) {
    868 		/* cache simply not present */
    869 		*addr = 0;
    870 		return 0;
    871 	}
    872 
    873 	ccb = nvme_ccb_get(q, true);
    874 	KASSERT(ccb != NULL);
    875 
    876 	ccb->ccb_done = nvme_getcache_done;
    877 	ccb->ccb_cookie = &result;
    878 
    879 	/* namespace context */
    880 	ccb->nnc_flags = 0;
    881 	ccb->nnc_done = NULL;
    882 
    883 	nvme_q_submit(sc, q, ccb, nvme_getcache_fill);
    884 
    885 	/* wait for completion */
    886 	nvme_q_wait_complete(sc, q, nvme_getcache_finished, &result);
    887 	KASSERT(result != 0);
    888 
    889 	if (result > 0) {
    890 		*addr = result;
    891 		error = 0;
    892 	} else
    893 		error = EINVAL;
    894 
    895 	return error;
    896 }
    897 
    898 static void
    899 nvme_getcache_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
    900 {
    901 	struct nvme_sqe *sqe = slot;
    902 
    903 	sqe->opcode = NVM_ADMIN_GET_FEATURES;
    904 	htolem32(&sqe->cdw10, NVM_FEATURE_VOLATILE_WRITE_CACHE);
    905 }
    906 
    907 static void
    908 nvme_getcache_done(struct nvme_queue *q, struct nvme_ccb *ccb,
    909     struct nvme_cqe *cqe)
    910 {
    911 	int *addr = ccb->ccb_cookie;
    912 	uint16_t status = NVME_CQE_SC(lemtoh16(&cqe->flags));
    913 	uint32_t cdw0 = lemtoh32(&cqe->cdw0);
    914 	int result;
    915 
    916 	if (status == NVME_CQE_SC_SUCCESS) {
    917 		result = 0;
    918 
    919 		/*
    920 		 * DPO not supported, Dataset Management (DSM) field doesn't
    921 		 * specify the same semantics. FUA is always supported.
    922 		 */
    923 		result = DKCACHE_FUA;
    924 
    925 		if (cdw0 & NVME_CQE_CDW0_VWC_WCE)
    926 			result |= DKCACHE_WRITE;
    927 
    928 		/*
    929 		 * If volatile write cache is present, the flag shall also be
    930 		 * settable.
    931 		 */
    932 		result |= DKCACHE_WCHANGE;
    933 	} else {
    934 		result = -1;
    935 	}
    936 
    937 	*addr = result;
    938 
    939 	nvme_ccb_put(q, ccb);
    940 }
    941 
    942 void
    943 nvme_ns_free(struct nvme_softc *sc, uint16_t nsid)
    944 {
    945 	struct nvme_namespace *ns;
    946 	struct nvm_identify_namespace *identify;
    947 
    948 	ns = nvme_ns_get(sc, nsid);
    949 	KASSERT(ns);
    950 
    951 	identify = ns->ident;
    952 	ns->ident = NULL;
    953 	if (identify != NULL)
    954 		kmem_free(identify, sizeof(*identify));
    955 }
    956 
    957 struct nvme_pt_state {
    958 	struct nvme_pt_command *pt;
    959 	bool finished;
    960 };
    961 
    962 static void
    963 nvme_pt_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
    964 {
    965 	struct nvme_softc *sc = q->q_sc;
    966 	struct nvme_sqe *sqe = slot;
    967 	struct nvme_pt_state *state = ccb->ccb_cookie;
    968 	struct nvme_pt_command *pt = state->pt;
    969 	bus_dmamap_t dmap = ccb->ccb_dmamap;
    970 	int i;
    971 
    972 	sqe->opcode = pt->cmd.opcode;
    973 	htolem32(&sqe->nsid, pt->cmd.nsid);
    974 
    975 	if (pt->buf != NULL && pt->len > 0) {
    976 		htolem64(&sqe->entry.prp[0], dmap->dm_segs[0].ds_addr);
    977 		switch (dmap->dm_nsegs) {
    978 		case 1:
    979 			break;
    980 		case 2:
    981 			htolem64(&sqe->entry.prp[1], dmap->dm_segs[1].ds_addr);
    982 			break;
    983 		default:
    984 			for (i = 1; i < dmap->dm_nsegs; i++) {
    985 				htolem64(&ccb->ccb_prpl[i - 1],
    986 				    dmap->dm_segs[i].ds_addr);
    987 			}
    988 			bus_dmamap_sync(sc->sc_dmat,
    989 			    NVME_DMA_MAP(q->q_ccb_prpls),
    990 			    ccb->ccb_prpl_off,
    991 			    sizeof(*ccb->ccb_prpl) * (dmap->dm_nsegs - 1),
    992 			    BUS_DMASYNC_PREWRITE);
    993 			htolem64(&sqe->entry.prp[1], ccb->ccb_prpl_dva);
    994 			break;
    995 		}
    996 	}
    997 
    998 	htolem32(&sqe->cdw10, pt->cmd.cdw10);
    999 	htolem32(&sqe->cdw11, pt->cmd.cdw11);
   1000 	htolem32(&sqe->cdw12, pt->cmd.cdw12);
   1001 	htolem32(&sqe->cdw13, pt->cmd.cdw13);
   1002 	htolem32(&sqe->cdw14, pt->cmd.cdw14);
   1003 	htolem32(&sqe->cdw15, pt->cmd.cdw15);
   1004 }
   1005 
   1006 static void
   1007 nvme_pt_done(struct nvme_queue *q, struct nvme_ccb *ccb, struct nvme_cqe *cqe)
   1008 {
   1009 	struct nvme_softc *sc = q->q_sc;
   1010 	struct nvme_pt_state *state = ccb->ccb_cookie;
   1011 	struct nvme_pt_command *pt = state->pt;
   1012 	bus_dmamap_t dmap = ccb->ccb_dmamap;
   1013 
   1014 	if (pt->buf != NULL && pt->len > 0) {
   1015 		if (dmap->dm_nsegs > 2) {
   1016 			bus_dmamap_sync(sc->sc_dmat,
   1017 			    NVME_DMA_MAP(q->q_ccb_prpls),
   1018 			    ccb->ccb_prpl_off,
   1019 			    sizeof(*ccb->ccb_prpl) * (dmap->dm_nsegs - 1),
   1020 			    BUS_DMASYNC_POSTWRITE);
   1021 		}
   1022 
   1023 		bus_dmamap_sync(sc->sc_dmat, dmap, 0, dmap->dm_mapsize,
   1024 		    pt->is_read ? BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
   1025 		bus_dmamap_unload(sc->sc_dmat, dmap);
   1026 	}
   1027 
   1028 	pt->cpl.cdw0 = lemtoh32(&cqe->cdw0);
   1029 	pt->cpl.flags = lemtoh16(&cqe->flags) & ~NVME_CQE_PHASE;
   1030 
   1031 	state->finished = true;
   1032 
   1033 	nvme_ccb_put(q, ccb);
   1034 }
   1035 
   1036 static bool
   1037 nvme_pt_finished(void *cookie)
   1038 {
   1039 	struct nvme_pt_state *state = cookie;
   1040 
   1041 	return state->finished;
   1042 }
   1043 
   1044 static int
   1045 nvme_command_passthrough(struct nvme_softc *sc, struct nvme_pt_command *pt,
   1046     uint16_t nsid, struct lwp *l, bool is_adminq)
   1047 {
   1048 	struct nvme_queue *q;
   1049 	struct nvme_ccb *ccb;
   1050 	void *buf = NULL;
   1051 	struct nvme_pt_state state;
   1052 	int error;
   1053 
   1054 	/* limit command size to maximum data transfer size */
   1055 	if ((pt->buf == NULL && pt->len > 0) ||
   1056 	    (pt->buf != NULL && (pt->len == 0 || pt->len > sc->sc_mdts)))
   1057 		return EINVAL;
   1058 
   1059 	q = is_adminq ? sc->sc_admin_q : nvme_get_q(sc);
   1060 	ccb = nvme_ccb_get(q, true);
   1061 	KASSERT(ccb != NULL);
   1062 
   1063 	if (pt->buf != NULL) {
   1064 		KASSERT(pt->len > 0);
   1065 		buf = kmem_alloc(pt->len, KM_SLEEP);
   1066 		if (!pt->is_read) {
   1067 			error = copyin(pt->buf, buf, pt->len);
   1068 			if (error)
   1069 				goto kmem_free;
   1070 		}
   1071 		error = bus_dmamap_load(sc->sc_dmat, ccb->ccb_dmamap, buf,
   1072 		    pt->len, NULL,
   1073 		    BUS_DMA_WAITOK |
   1074 		      (pt->is_read ? BUS_DMA_READ : BUS_DMA_WRITE));
   1075 		if (error)
   1076 			goto kmem_free;
   1077 		bus_dmamap_sync(sc->sc_dmat, ccb->ccb_dmamap,
   1078 		    0, ccb->ccb_dmamap->dm_mapsize,
   1079 		    pt->is_read ? BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
   1080 	}
   1081 
   1082 	memset(&state, 0, sizeof(state));
   1083 	state.pt = pt;
   1084 	state.finished = false;
   1085 
   1086 	ccb->ccb_done = nvme_pt_done;
   1087 	ccb->ccb_cookie = &state;
   1088 
   1089 	pt->cmd.nsid = nsid;
   1090 
   1091 	nvme_q_submit(sc, q, ccb, nvme_pt_fill);
   1092 
   1093 	/* wait for completion */
   1094 	nvme_q_wait_complete(sc, q, nvme_pt_finished, &state);
   1095 	KASSERT(state.finished);
   1096 
   1097 	error = 0;
   1098 
   1099 	if (buf != NULL) {
   1100 		if (error == 0 && pt->is_read)
   1101 			error = copyout(buf, pt->buf, pt->len);
   1102 kmem_free:
   1103 		kmem_free(buf, pt->len);
   1104 	}
   1105 
   1106 	return error;
   1107 }
   1108 
   1109 static void
   1110 nvme_q_submit(struct nvme_softc *sc, struct nvme_queue *q, struct nvme_ccb *ccb,
   1111     void (*fill)(struct nvme_queue *, struct nvme_ccb *, void *))
   1112 {
   1113 	struct nvme_sqe *sqe = NVME_DMA_KVA(q->q_sq_dmamem);
   1114 	uint32_t tail;
   1115 
   1116 	mutex_enter(&q->q_sq_mtx);
   1117 	tail = q->q_sq_tail;
   1118 	if (++q->q_sq_tail >= q->q_entries)
   1119 		q->q_sq_tail = 0;
   1120 
   1121 	sqe += tail;
   1122 
   1123 	bus_dmamap_sync(sc->sc_dmat, NVME_DMA_MAP(q->q_sq_dmamem),
   1124 	    sizeof(*sqe) * tail, sizeof(*sqe), BUS_DMASYNC_POSTWRITE);
   1125 	memset(sqe, 0, sizeof(*sqe));
   1126 	(*fill)(q, ccb, sqe);
   1127 	htolem16(&sqe->cid, ccb->ccb_id);
   1128 	bus_dmamap_sync(sc->sc_dmat, NVME_DMA_MAP(q->q_sq_dmamem),
   1129 	    sizeof(*sqe) * tail, sizeof(*sqe), BUS_DMASYNC_PREWRITE);
   1130 
   1131 	nvme_write4(sc, q->q_sqtdbl, q->q_sq_tail);
   1132 	mutex_exit(&q->q_sq_mtx);
   1133 }
   1134 
   1135 struct nvme_poll_state {
   1136 	struct nvme_sqe s;
   1137 	struct nvme_cqe c;
   1138 	void *cookie;
   1139 	void (*done)(struct nvme_queue *, struct nvme_ccb *, struct nvme_cqe *);
   1140 };
   1141 
   1142 static int
   1143 nvme_poll(struct nvme_softc *sc, struct nvme_queue *q, struct nvme_ccb *ccb,
   1144     void (*fill)(struct nvme_queue *, struct nvme_ccb *, void *), int timo_sec)
   1145 {
   1146 	struct nvme_poll_state state;
   1147 	uint16_t flags;
   1148 	int step = 10;
   1149 	int maxloop = timo_sec * 1000000 / step;
   1150 	int error = 0;
   1151 
   1152 	memset(&state, 0, sizeof(state));
   1153 	(*fill)(q, ccb, &state.s);
   1154 
   1155 	state.done = ccb->ccb_done;
   1156 	state.cookie = ccb->ccb_cookie;
   1157 
   1158 	ccb->ccb_done = nvme_poll_done;
   1159 	ccb->ccb_cookie = &state;
   1160 
   1161 	nvme_q_submit(sc, q, ccb, nvme_poll_fill);
   1162 	while (!ISSET(state.c.flags, htole16(NVME_CQE_PHASE))) {
   1163 		if (nvme_q_complete(sc, q) == 0)
   1164 			delay(step);
   1165 
   1166 		if (timo_sec >= 0 && --maxloop <= 0) {
   1167 			error = ETIMEDOUT;
   1168 			break;
   1169 		}
   1170 	}
   1171 
   1172 	if (error == 0) {
   1173 		flags = lemtoh16(&state.c.flags);
   1174 		return flags & ~NVME_CQE_PHASE;
   1175 	} else {
   1176 		/*
   1177 		 * If it succeds later, it would hit ccb which will have been
   1178 		 * already reused for something else. Not good. Cross
   1179 		 * fingers and hope for best. XXX do controller reset?
   1180 		 */
   1181 		aprint_error_dev(sc->sc_dev, "polled command timed out\n");
   1182 
   1183 		/* Invoke the callback to clean state anyway */
   1184 		struct nvme_cqe cqe;
   1185 		memset(&cqe, 0, sizeof(cqe));
   1186 		ccb->ccb_done(q, ccb, &cqe);
   1187 
   1188 		return 1;
   1189 	}
   1190 }
   1191 
   1192 static void
   1193 nvme_poll_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
   1194 {
   1195 	struct nvme_sqe *sqe = slot;
   1196 	struct nvme_poll_state *state = ccb->ccb_cookie;
   1197 
   1198 	*sqe = state->s;
   1199 }
   1200 
   1201 static void
   1202 nvme_poll_done(struct nvme_queue *q, struct nvme_ccb *ccb,
   1203     struct nvme_cqe *cqe)
   1204 {
   1205 	struct nvme_poll_state *state = ccb->ccb_cookie;
   1206 
   1207 	SET(cqe->flags, htole16(NVME_CQE_PHASE));
   1208 	state->c = *cqe;
   1209 
   1210 	ccb->ccb_cookie = state->cookie;
   1211 	state->done(q, ccb, &state->c);
   1212 }
   1213 
   1214 static void
   1215 nvme_sqe_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
   1216 {
   1217 	struct nvme_sqe *src = ccb->ccb_cookie;
   1218 	struct nvme_sqe *dst = slot;
   1219 
   1220 	*dst = *src;
   1221 }
   1222 
   1223 static void
   1224 nvme_empty_done(struct nvme_queue *q, struct nvme_ccb *ccb,
   1225     struct nvme_cqe *cqe)
   1226 {
   1227 }
   1228 
   1229 static int
   1230 nvme_q_complete(struct nvme_softc *sc, struct nvme_queue *q)
   1231 {
   1232 	struct nvme_ccb *ccb;
   1233 	struct nvme_cqe *ring = NVME_DMA_KVA(q->q_cq_dmamem), *cqe;
   1234 	uint16_t flags;
   1235 	int rv = 0;
   1236 
   1237 	mutex_enter(&q->q_cq_mtx);
   1238 
   1239 	nvme_dmamem_sync(sc, q->q_cq_dmamem, BUS_DMASYNC_POSTREAD);
   1240 	for (;;) {
   1241 		cqe = &ring[q->q_cq_head];
   1242 		flags = lemtoh16(&cqe->flags);
   1243 		if ((flags & NVME_CQE_PHASE) != q->q_cq_phase)
   1244 			break;
   1245 
   1246 		ccb = &q->q_ccbs[cqe->cid];
   1247 
   1248 		if (++q->q_cq_head >= q->q_entries) {
   1249 			q->q_cq_head = 0;
   1250 			q->q_cq_phase ^= NVME_CQE_PHASE;
   1251 		}
   1252 
   1253 #ifdef DEBUG
   1254 		/*
   1255 		 * If we get spurious completion notification, something
   1256 		 * is seriously hosed up. Very likely DMA to some random
   1257 		 * memory place happened, so just bail out.
   1258 		 */
   1259 		if ((intptr_t)ccb->ccb_cookie == NVME_CCB_FREE) {
   1260 			panic("%s: invalid ccb detected",
   1261 			    device_xname(sc->sc_dev));
   1262 			/* NOTREACHED */
   1263 		}
   1264 #endif
   1265 
   1266 		rv++;
   1267 
   1268 		/*
   1269 		 * Unlock the mutex before calling the ccb_done callback
   1270 		 * and re-lock afterwards. The callback triggers lddone()
   1271 		 * which schedules another i/o, and also calls nvme_ccb_put().
   1272 		 * Unlock/relock avoids possibility of deadlock.
   1273 		 */
   1274 		mutex_exit(&q->q_cq_mtx);
   1275 		ccb->ccb_done(q, ccb, cqe);
   1276 		mutex_enter(&q->q_cq_mtx);
   1277 	}
   1278 	nvme_dmamem_sync(sc, q->q_cq_dmamem, BUS_DMASYNC_PREREAD);
   1279 
   1280 	if (rv)
   1281 		nvme_write4(sc, q->q_cqhdbl, q->q_cq_head);
   1282 
   1283 	mutex_exit(&q->q_cq_mtx);
   1284 
   1285 	return rv;
   1286 }
   1287 
   1288 static void
   1289 nvme_q_wait_complete(struct nvme_softc *sc,
   1290     struct nvme_queue *q, bool (*finished)(void *), void *cookie)
   1291 {
   1292 	mutex_enter(&q->q_ccb_mtx);
   1293 	if (finished(cookie))
   1294 		goto out;
   1295 
   1296 	for(;;) {
   1297 		q->q_ccb_waiting = true;
   1298 		cv_wait(&q->q_ccb_wait, &q->q_ccb_mtx);
   1299 
   1300 		if (finished(cookie))
   1301 			break;
   1302 	}
   1303 
   1304 out:
   1305 	mutex_exit(&q->q_ccb_mtx);
   1306 }
   1307 
   1308 static int
   1309 nvme_identify(struct nvme_softc *sc, u_int mps)
   1310 {
   1311 	char sn[41], mn[81], fr[17];
   1312 	struct nvm_identify_controller *identify;
   1313 	struct nvme_dmamem *mem;
   1314 	struct nvme_ccb *ccb;
   1315 	u_int mdts;
   1316 	int rv = 1;
   1317 
   1318 	ccb = nvme_ccb_get(sc->sc_admin_q, false);
   1319 	KASSERT(ccb != NULL); /* it's a bug if we don't have spare ccb here */
   1320 
   1321 	mem = nvme_dmamem_alloc(sc, sizeof(*identify));
   1322 	if (mem == NULL)
   1323 		return 1;
   1324 
   1325 	ccb->ccb_done = nvme_empty_done;
   1326 	ccb->ccb_cookie = mem;
   1327 
   1328 	nvme_dmamem_sync(sc, mem, BUS_DMASYNC_PREREAD);
   1329 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_fill_identify,
   1330 	    NVME_TIMO_IDENT);
   1331 	nvme_dmamem_sync(sc, mem, BUS_DMASYNC_POSTREAD);
   1332 
   1333 	nvme_ccb_put(sc->sc_admin_q, ccb);
   1334 
   1335 	if (rv != 0)
   1336 		goto done;
   1337 
   1338 	identify = NVME_DMA_KVA(mem);
   1339 	sc->sc_identify = *identify;
   1340 	identify = NULL;
   1341 
   1342 	/* Convert data to host endian */
   1343 	nvme_identify_controller_swapbytes(&sc->sc_identify);
   1344 
   1345 	strnvisx(sn, sizeof(sn), (const char *)sc->sc_identify.sn,
   1346 	    sizeof(sc->sc_identify.sn), VIS_TRIM|VIS_SAFE|VIS_OCTAL);
   1347 	strnvisx(mn, sizeof(mn), (const char *)sc->sc_identify.mn,
   1348 	    sizeof(sc->sc_identify.mn), VIS_TRIM|VIS_SAFE|VIS_OCTAL);
   1349 	strnvisx(fr, sizeof(fr), (const char *)sc->sc_identify.fr,
   1350 	    sizeof(sc->sc_identify.fr), VIS_TRIM|VIS_SAFE|VIS_OCTAL);
   1351 	aprint_normal_dev(sc->sc_dev, "%s, firmware %s, serial %s\n", mn, fr,
   1352 	    sn);
   1353 
   1354 	if (sc->sc_identify.mdts > 0) {
   1355 		mdts = (1 << sc->sc_identify.mdts) * (1 << mps);
   1356 		if (mdts < sc->sc_mdts)
   1357 			sc->sc_mdts = mdts;
   1358 	}
   1359 
   1360 	sc->sc_nn = sc->sc_identify.nn;
   1361 
   1362 done:
   1363 	nvme_dmamem_free(sc, mem);
   1364 
   1365 	return rv;
   1366 }
   1367 
   1368 static int
   1369 nvme_q_create(struct nvme_softc *sc, struct nvme_queue *q)
   1370 {
   1371 	struct nvme_sqe_q sqe;
   1372 	struct nvme_ccb *ccb;
   1373 	int rv;
   1374 
   1375 	if (sc->sc_use_mq && sc->sc_intr_establish(sc, q->q_id, q) != 0)
   1376 		return 1;
   1377 
   1378 	ccb = nvme_ccb_get(sc->sc_admin_q, false);
   1379 	KASSERT(ccb != NULL);
   1380 
   1381 	ccb->ccb_done = nvme_empty_done;
   1382 	ccb->ccb_cookie = &sqe;
   1383 
   1384 	memset(&sqe, 0, sizeof(sqe));
   1385 	sqe.opcode = NVM_ADMIN_ADD_IOCQ;
   1386 	htolem64(&sqe.prp1, NVME_DMA_DVA(q->q_cq_dmamem));
   1387 	htolem16(&sqe.qsize, q->q_entries - 1);
   1388 	htolem16(&sqe.qid, q->q_id);
   1389 	sqe.qflags = NVM_SQE_CQ_IEN | NVM_SQE_Q_PC;
   1390 	if (sc->sc_use_mq)
   1391 		htolem16(&sqe.cqid, q->q_id);	/* qid == vector */
   1392 
   1393 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_sqe_fill, NVME_TIMO_QOP);
   1394 	if (rv != 0)
   1395 		goto fail;
   1396 
   1397 	ccb->ccb_done = nvme_empty_done;
   1398 	ccb->ccb_cookie = &sqe;
   1399 
   1400 	memset(&sqe, 0, sizeof(sqe));
   1401 	sqe.opcode = NVM_ADMIN_ADD_IOSQ;
   1402 	htolem64(&sqe.prp1, NVME_DMA_DVA(q->q_sq_dmamem));
   1403 	htolem16(&sqe.qsize, q->q_entries - 1);
   1404 	htolem16(&sqe.qid, q->q_id);
   1405 	htolem16(&sqe.cqid, q->q_id);
   1406 	sqe.qflags = NVM_SQE_Q_PC;
   1407 
   1408 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_sqe_fill, NVME_TIMO_QOP);
   1409 	if (rv != 0)
   1410 		goto fail;
   1411 
   1412 fail:
   1413 	nvme_ccb_put(sc->sc_admin_q, ccb);
   1414 	return rv;
   1415 }
   1416 
   1417 static int
   1418 nvme_q_delete(struct nvme_softc *sc, struct nvme_queue *q)
   1419 {
   1420 	struct nvme_sqe_q sqe;
   1421 	struct nvme_ccb *ccb;
   1422 	int rv;
   1423 
   1424 	ccb = nvme_ccb_get(sc->sc_admin_q, false);
   1425 	KASSERT(ccb != NULL);
   1426 
   1427 	ccb->ccb_done = nvme_empty_done;
   1428 	ccb->ccb_cookie = &sqe;
   1429 
   1430 	memset(&sqe, 0, sizeof(sqe));
   1431 	sqe.opcode = NVM_ADMIN_DEL_IOSQ;
   1432 	htolem16(&sqe.qid, q->q_id);
   1433 
   1434 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_sqe_fill, NVME_TIMO_QOP);
   1435 	if (rv != 0)
   1436 		goto fail;
   1437 
   1438 	ccb->ccb_done = nvme_empty_done;
   1439 	ccb->ccb_cookie = &sqe;
   1440 
   1441 	memset(&sqe, 0, sizeof(sqe));
   1442 	sqe.opcode = NVM_ADMIN_DEL_IOCQ;
   1443 	htolem16(&sqe.qid, q->q_id);
   1444 
   1445 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_sqe_fill, NVME_TIMO_QOP);
   1446 	if (rv != 0)
   1447 		goto fail;
   1448 
   1449 fail:
   1450 	nvme_ccb_put(sc->sc_admin_q, ccb);
   1451 
   1452 	if (rv == 0 && sc->sc_use_mq) {
   1453 		if (sc->sc_intr_disestablish(sc, q->q_id))
   1454 			rv = 1;
   1455 	}
   1456 
   1457 	return rv;
   1458 }
   1459 
   1460 static void
   1461 nvme_fill_identify(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
   1462 {
   1463 	struct nvme_sqe *sqe = slot;
   1464 	struct nvme_dmamem *mem = ccb->ccb_cookie;
   1465 
   1466 	sqe->opcode = NVM_ADMIN_IDENTIFY;
   1467 	htolem64(&sqe->entry.prp[0], NVME_DMA_DVA(mem));
   1468 	htolem32(&sqe->cdw10, 1);
   1469 }
   1470 
   1471 static int
   1472 nvme_get_number_of_queues(struct nvme_softc *sc, u_int *nqap)
   1473 {
   1474 	struct nvme_pt_state state;
   1475 	struct nvme_pt_command pt;
   1476 	struct nvme_ccb *ccb;
   1477 	uint16_t ncqa, nsqa;
   1478 	int rv;
   1479 
   1480 	ccb = nvme_ccb_get(sc->sc_admin_q, false);
   1481 	KASSERT(ccb != NULL); /* it's a bug if we don't have spare ccb here */
   1482 
   1483 	memset(&pt, 0, sizeof(pt));
   1484 	pt.cmd.opcode = NVM_ADMIN_GET_FEATURES;
   1485 	pt.cmd.cdw10 = NVM_FEATURE_NUMBER_OF_QUEUES;
   1486 
   1487 	memset(&state, 0, sizeof(state));
   1488 	state.pt = &pt;
   1489 	state.finished = false;
   1490 
   1491 	ccb->ccb_done = nvme_pt_done;
   1492 	ccb->ccb_cookie = &state;
   1493 
   1494 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_pt_fill, NVME_TIMO_QOP);
   1495 
   1496 	if (rv != 0) {
   1497 		*nqap = 0;
   1498 		return EIO;
   1499 	}
   1500 
   1501 	ncqa = pt.cpl.cdw0 >> 16;
   1502 	nsqa = pt.cpl.cdw0 & 0xffff;
   1503 	*nqap = MIN(ncqa, nsqa) + 1;
   1504 
   1505 	return 0;
   1506 }
   1507 
   1508 static int
   1509 nvme_ccbs_alloc(struct nvme_queue *q, uint16_t nccbs)
   1510 {
   1511 	struct nvme_softc *sc = q->q_sc;
   1512 	struct nvme_ccb *ccb;
   1513 	bus_addr_t off;
   1514 	uint64_t *prpl;
   1515 	u_int i;
   1516 
   1517 	mutex_init(&q->q_ccb_mtx, MUTEX_DEFAULT, IPL_BIO);
   1518 	cv_init(&q->q_ccb_wait, "nvmeqw");
   1519 	q->q_ccb_waiting = false;
   1520 	SIMPLEQ_INIT(&q->q_ccb_list);
   1521 
   1522 	q->q_ccbs = kmem_alloc(sizeof(*ccb) * nccbs, KM_SLEEP);
   1523 
   1524 	q->q_nccbs = nccbs;
   1525 	q->q_ccb_prpls = nvme_dmamem_alloc(sc,
   1526 	    sizeof(*prpl) * sc->sc_max_sgl * nccbs);
   1527 
   1528 	prpl = NVME_DMA_KVA(q->q_ccb_prpls);
   1529 	off = 0;
   1530 
   1531 	for (i = 0; i < nccbs; i++) {
   1532 		ccb = &q->q_ccbs[i];
   1533 
   1534 		if (bus_dmamap_create(sc->sc_dmat, sc->sc_mdts,
   1535 		    sc->sc_max_sgl + 1 /* we get a free prp in the sqe */,
   1536 		    sc->sc_mps, sc->sc_mps, BUS_DMA_WAITOK | BUS_DMA_ALLOCNOW,
   1537 		    &ccb->ccb_dmamap) != 0)
   1538 			goto free_maps;
   1539 
   1540 		ccb->ccb_id = i;
   1541 		ccb->ccb_prpl = prpl;
   1542 		ccb->ccb_prpl_off = off;
   1543 		ccb->ccb_prpl_dva = NVME_DMA_DVA(q->q_ccb_prpls) + off;
   1544 
   1545 		SIMPLEQ_INSERT_TAIL(&q->q_ccb_list, ccb, ccb_entry);
   1546 
   1547 		prpl += sc->sc_max_sgl;
   1548 		off += sizeof(*prpl) * sc->sc_max_sgl;
   1549 	}
   1550 
   1551 	return 0;
   1552 
   1553 free_maps:
   1554 	nvme_ccbs_free(q);
   1555 	return 1;
   1556 }
   1557 
   1558 static struct nvme_ccb *
   1559 nvme_ccb_get(struct nvme_queue *q, bool wait)
   1560 {
   1561 	struct nvme_ccb *ccb = NULL;
   1562 
   1563 	mutex_enter(&q->q_ccb_mtx);
   1564 again:
   1565 	ccb = SIMPLEQ_FIRST(&q->q_ccb_list);
   1566 	if (ccb != NULL) {
   1567 		SIMPLEQ_REMOVE_HEAD(&q->q_ccb_list, ccb_entry);
   1568 #ifdef DEBUG
   1569 		ccb->ccb_cookie = NULL;
   1570 #endif
   1571 	} else {
   1572 		if (__predict_false(wait)) {
   1573 			q->q_ccb_waiting = true;
   1574 			cv_wait(&q->q_ccb_wait, &q->q_ccb_mtx);
   1575 			goto again;
   1576 		}
   1577 	}
   1578 	mutex_exit(&q->q_ccb_mtx);
   1579 
   1580 	return ccb;
   1581 }
   1582 
   1583 static void
   1584 nvme_ccb_put(struct nvme_queue *q, struct nvme_ccb *ccb)
   1585 {
   1586 
   1587 	mutex_enter(&q->q_ccb_mtx);
   1588 #ifdef DEBUG
   1589 	ccb->ccb_cookie = (void *)NVME_CCB_FREE;
   1590 #endif
   1591 	SIMPLEQ_INSERT_HEAD(&q->q_ccb_list, ccb, ccb_entry);
   1592 
   1593 	/* It's unlikely there are any waiters, it's not used for regular I/O */
   1594 	if (__predict_false(q->q_ccb_waiting)) {
   1595 		q->q_ccb_waiting = false;
   1596 		cv_broadcast(&q->q_ccb_wait);
   1597 	}
   1598 
   1599 	mutex_exit(&q->q_ccb_mtx);
   1600 }
   1601 
   1602 static void
   1603 nvme_ccbs_free(struct nvme_queue *q)
   1604 {
   1605 	struct nvme_softc *sc = q->q_sc;
   1606 	struct nvme_ccb *ccb;
   1607 
   1608 	mutex_enter(&q->q_ccb_mtx);
   1609 	while ((ccb = SIMPLEQ_FIRST(&q->q_ccb_list)) != NULL) {
   1610 		SIMPLEQ_REMOVE_HEAD(&q->q_ccb_list, ccb_entry);
   1611 		bus_dmamap_destroy(sc->sc_dmat, ccb->ccb_dmamap);
   1612 	}
   1613 	mutex_exit(&q->q_ccb_mtx);
   1614 
   1615 	nvme_dmamem_free(sc, q->q_ccb_prpls);
   1616 	kmem_free(q->q_ccbs, sizeof(*ccb) * q->q_nccbs);
   1617 	q->q_ccbs = NULL;
   1618 	cv_destroy(&q->q_ccb_wait);
   1619 	mutex_destroy(&q->q_ccb_mtx);
   1620 }
   1621 
   1622 static struct nvme_queue *
   1623 nvme_q_alloc(struct nvme_softc *sc, uint16_t id, u_int entries, u_int dstrd)
   1624 {
   1625 	struct nvme_queue *q;
   1626 
   1627 	q = kmem_alloc(sizeof(*q), KM_SLEEP);
   1628 	q->q_sc = sc;
   1629 	q->q_sq_dmamem = nvme_dmamem_alloc(sc,
   1630 	    sizeof(struct nvme_sqe) * entries);
   1631 	if (q->q_sq_dmamem == NULL)
   1632 		goto free;
   1633 
   1634 	q->q_cq_dmamem = nvme_dmamem_alloc(sc,
   1635 	    sizeof(struct nvme_cqe) * entries);
   1636 	if (q->q_cq_dmamem == NULL)
   1637 		goto free_sq;
   1638 
   1639 	memset(NVME_DMA_KVA(q->q_sq_dmamem), 0, NVME_DMA_LEN(q->q_sq_dmamem));
   1640 	memset(NVME_DMA_KVA(q->q_cq_dmamem), 0, NVME_DMA_LEN(q->q_cq_dmamem));
   1641 
   1642 	mutex_init(&q->q_sq_mtx, MUTEX_DEFAULT, IPL_BIO);
   1643 	mutex_init(&q->q_cq_mtx, MUTEX_DEFAULT, IPL_BIO);
   1644 	q->q_sqtdbl = NVME_SQTDBL(id, dstrd);
   1645 	q->q_cqhdbl = NVME_CQHDBL(id, dstrd);
   1646 	q->q_id = id;
   1647 	q->q_entries = entries;
   1648 	q->q_sq_tail = 0;
   1649 	q->q_cq_head = 0;
   1650 	q->q_cq_phase = NVME_CQE_PHASE;
   1651 
   1652 	nvme_dmamem_sync(sc, q->q_sq_dmamem, BUS_DMASYNC_PREWRITE);
   1653 	nvme_dmamem_sync(sc, q->q_cq_dmamem, BUS_DMASYNC_PREREAD);
   1654 
   1655 	/*
   1656 	 * Due to definition of full and empty queue (queue is empty
   1657 	 * when head == tail, full when tail is one less then head),
   1658 	 * we can actually only have (entries - 1) in-flight commands.
   1659 	 */
   1660 	if (nvme_ccbs_alloc(q, entries - 1) != 0) {
   1661 		aprint_error_dev(sc->sc_dev, "unable to allocate ccbs\n");
   1662 		goto free_cq;
   1663 	}
   1664 
   1665 	return q;
   1666 
   1667 free_cq:
   1668 	nvme_dmamem_free(sc, q->q_cq_dmamem);
   1669 free_sq:
   1670 	nvme_dmamem_free(sc, q->q_sq_dmamem);
   1671 free:
   1672 	kmem_free(q, sizeof(*q));
   1673 
   1674 	return NULL;
   1675 }
   1676 
   1677 static void
   1678 nvme_q_free(struct nvme_softc *sc, struct nvme_queue *q)
   1679 {
   1680 	nvme_ccbs_free(q);
   1681 	mutex_destroy(&q->q_sq_mtx);
   1682 	mutex_destroy(&q->q_cq_mtx);
   1683 	nvme_dmamem_sync(sc, q->q_cq_dmamem, BUS_DMASYNC_POSTREAD);
   1684 	nvme_dmamem_sync(sc, q->q_sq_dmamem, BUS_DMASYNC_POSTWRITE);
   1685 	nvme_dmamem_free(sc, q->q_cq_dmamem);
   1686 	nvme_dmamem_free(sc, q->q_sq_dmamem);
   1687 	kmem_free(q, sizeof(*q));
   1688 }
   1689 
   1690 int
   1691 nvme_intr(void *xsc)
   1692 {
   1693 	struct nvme_softc *sc = xsc;
   1694 
   1695 	/*
   1696 	 * INTx is level triggered, controller deasserts the interrupt only
   1697 	 * when we advance command queue head via write to the doorbell.
   1698 	 * Tell the controller to block the interrupts while we process
   1699 	 * the queue(s).
   1700 	 */
   1701 	nvme_write4(sc, NVME_INTMS, 1);
   1702 
   1703 	softint_schedule(sc->sc_softih[0]);
   1704 
   1705 	/* don't know, might not have been for us */
   1706 	return 1;
   1707 }
   1708 
   1709 void
   1710 nvme_softintr_intx(void *xq)
   1711 {
   1712 	struct nvme_queue *q = xq;
   1713 	struct nvme_softc *sc = q->q_sc;
   1714 
   1715 	nvme_q_complete(sc, sc->sc_admin_q);
   1716 	if (sc->sc_q != NULL)
   1717 	        nvme_q_complete(sc, sc->sc_q[0]);
   1718 
   1719 	/*
   1720 	 * Processing done, tell controller to issue interrupts again. There
   1721 	 * is no race, as NVMe spec requires the controller to maintain state,
   1722 	 * and assert the interrupt whenever there are unacknowledged
   1723 	 * completion queue entries.
   1724 	 */
   1725 	nvme_write4(sc, NVME_INTMC, 1);
   1726 }
   1727 
   1728 int
   1729 nvme_intr_msi(void *xq)
   1730 {
   1731 	struct nvme_queue *q = xq;
   1732 
   1733 	KASSERT(q && q->q_sc && q->q_sc->sc_softih
   1734 	    && q->q_sc->sc_softih[q->q_id]);
   1735 
   1736 	/*
   1737 	 * MSI/MSI-X are edge triggered, so can handover processing to softint
   1738 	 * without masking the interrupt.
   1739 	 */
   1740 	softint_schedule(q->q_sc->sc_softih[q->q_id]);
   1741 
   1742 	return 1;
   1743 }
   1744 
   1745 void
   1746 nvme_softintr_msi(void *xq)
   1747 {
   1748 	struct nvme_queue *q = xq;
   1749 	struct nvme_softc *sc = q->q_sc;
   1750 
   1751 	nvme_q_complete(sc, q);
   1752 }
   1753 
   1754 static struct nvme_dmamem *
   1755 nvme_dmamem_alloc(struct nvme_softc *sc, size_t size)
   1756 {
   1757 	struct nvme_dmamem *ndm;
   1758 	int nsegs;
   1759 
   1760 	ndm = kmem_zalloc(sizeof(*ndm), KM_SLEEP);
   1761 	if (ndm == NULL)
   1762 		return NULL;
   1763 
   1764 	ndm->ndm_size = size;
   1765 
   1766 	if (bus_dmamap_create(sc->sc_dmat, size, 1, size, 0,
   1767 	    BUS_DMA_WAITOK | BUS_DMA_ALLOCNOW, &ndm->ndm_map) != 0)
   1768 		goto ndmfree;
   1769 
   1770 	if (bus_dmamem_alloc(sc->sc_dmat, size, sc->sc_mps, 0, &ndm->ndm_seg,
   1771 	    1, &nsegs, BUS_DMA_WAITOK) != 0)
   1772 		goto destroy;
   1773 
   1774 	if (bus_dmamem_map(sc->sc_dmat, &ndm->ndm_seg, nsegs, size,
   1775 	    &ndm->ndm_kva, BUS_DMA_WAITOK) != 0)
   1776 		goto free;
   1777 	memset(ndm->ndm_kva, 0, size);
   1778 
   1779 	if (bus_dmamap_load(sc->sc_dmat, ndm->ndm_map, ndm->ndm_kva, size,
   1780 	    NULL, BUS_DMA_WAITOK) != 0)
   1781 		goto unmap;
   1782 
   1783 	return ndm;
   1784 
   1785 unmap:
   1786 	bus_dmamem_unmap(sc->sc_dmat, ndm->ndm_kva, size);
   1787 free:
   1788 	bus_dmamem_free(sc->sc_dmat, &ndm->ndm_seg, 1);
   1789 destroy:
   1790 	bus_dmamap_destroy(sc->sc_dmat, ndm->ndm_map);
   1791 ndmfree:
   1792 	kmem_free(ndm, sizeof(*ndm));
   1793 	return NULL;
   1794 }
   1795 
   1796 static void
   1797 nvme_dmamem_sync(struct nvme_softc *sc, struct nvme_dmamem *mem, int ops)
   1798 {
   1799 	bus_dmamap_sync(sc->sc_dmat, NVME_DMA_MAP(mem),
   1800 	    0, NVME_DMA_LEN(mem), ops);
   1801 }
   1802 
   1803 void
   1804 nvme_dmamem_free(struct nvme_softc *sc, struct nvme_dmamem *ndm)
   1805 {
   1806 	bus_dmamap_unload(sc->sc_dmat, ndm->ndm_map);
   1807 	bus_dmamem_unmap(sc->sc_dmat, ndm->ndm_kva, ndm->ndm_size);
   1808 	bus_dmamem_free(sc->sc_dmat, &ndm->ndm_seg, 1);
   1809 	bus_dmamap_destroy(sc->sc_dmat, ndm->ndm_map);
   1810 	kmem_free(ndm, sizeof(*ndm));
   1811 }
   1812 
   1813 /*
   1814  * ioctl
   1815  */
   1816 
   1817 dev_type_open(nvmeopen);
   1818 dev_type_close(nvmeclose);
   1819 dev_type_ioctl(nvmeioctl);
   1820 
   1821 const struct cdevsw nvme_cdevsw = {
   1822 	.d_open = nvmeopen,
   1823 	.d_close = nvmeclose,
   1824 	.d_read = noread,
   1825 	.d_write = nowrite,
   1826 	.d_ioctl = nvmeioctl,
   1827 	.d_stop = nostop,
   1828 	.d_tty = notty,
   1829 	.d_poll = nopoll,
   1830 	.d_mmap = nommap,
   1831 	.d_kqfilter = nokqfilter,
   1832 	.d_discard = nodiscard,
   1833 	.d_flag = D_OTHER,
   1834 };
   1835 
   1836 /*
   1837  * Accept an open operation on the control device.
   1838  */
   1839 int
   1840 nvmeopen(dev_t dev, int flag, int mode, struct lwp *l)
   1841 {
   1842 	struct nvme_softc *sc;
   1843 	int unit = minor(dev) / 0x10000;
   1844 	int nsid = minor(dev) & 0xffff;
   1845 	int nsidx;
   1846 
   1847 	if ((sc = device_lookup_private(&nvme_cd, unit)) == NULL)
   1848 		return ENXIO;
   1849 	if ((sc->sc_flags & NVME_F_ATTACHED) == 0)
   1850 		return ENXIO;
   1851 
   1852 	if (nsid == 0) {
   1853 		/* controller */
   1854 		if (ISSET(sc->sc_flags, NVME_F_OPEN))
   1855 			return EBUSY;
   1856 		SET(sc->sc_flags, NVME_F_OPEN);
   1857 	} else {
   1858 		/* namespace */
   1859 		nsidx = nsid - 1;
   1860 		if (nsidx >= sc->sc_nn || sc->sc_namespaces[nsidx].dev == NULL)
   1861 			return ENXIO;
   1862 		if (ISSET(sc->sc_namespaces[nsidx].flags, NVME_NS_F_OPEN))
   1863 			return EBUSY;
   1864 		SET(sc->sc_namespaces[nsidx].flags, NVME_NS_F_OPEN);
   1865 	}
   1866 	return 0;
   1867 }
   1868 
   1869 /*
   1870  * Accept the last close on the control device.
   1871  */
   1872 int
   1873 nvmeclose(dev_t dev, int flag, int mode, struct lwp *l)
   1874 {
   1875 	struct nvme_softc *sc;
   1876 	int unit = minor(dev) / 0x10000;
   1877 	int nsid = minor(dev) & 0xffff;
   1878 	int nsidx;
   1879 
   1880 	sc = device_lookup_private(&nvme_cd, unit);
   1881 	if (sc == NULL)
   1882 		return ENXIO;
   1883 
   1884 	if (nsid == 0) {
   1885 		/* controller */
   1886 		CLR(sc->sc_flags, NVME_F_OPEN);
   1887 	} else {
   1888 		/* namespace */
   1889 		nsidx = nsid - 1;
   1890 		if (nsidx >= sc->sc_nn)
   1891 			return ENXIO;
   1892 		CLR(sc->sc_namespaces[nsidx].flags, NVME_NS_F_OPEN);
   1893 	}
   1894 
   1895 	return 0;
   1896 }
   1897 
   1898 /*
   1899  * Handle control operations.
   1900  */
   1901 int
   1902 nvmeioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
   1903 {
   1904 	struct nvme_softc *sc;
   1905 	int unit = minor(dev) / 0x10000;
   1906 	int nsid = minor(dev) & 0xffff;
   1907 	struct nvme_pt_command *pt;
   1908 
   1909 	sc = device_lookup_private(&nvme_cd, unit);
   1910 	if (sc == NULL)
   1911 		return ENXIO;
   1912 
   1913 	switch (cmd) {
   1914 	case NVME_PASSTHROUGH_CMD:
   1915 		pt = data;
   1916 		return nvme_command_passthrough(sc, data,
   1917 		    nsid == 0 ? pt->cmd.nsid : nsid, l, nsid == 0);
   1918 	}
   1919 
   1920 	return ENOTTY;
   1921 }
   1922