xref: /src/sys/arch/arc/TODO

$NetBSD: TODO,v 1.29 2011/01/08 09:44:37 tsutsui Exp $

To do list (in some particular order)
XXX some entries might be obsolete.

    o	use MI driver

	-   make fd driver MI, and share it with other ports
	    (contact christos about MI fd driver)

	-   use MI bha driver instead of home grown btl
	    XXX needs fixes of DESKstation support

    o	VXL framebuffer support (Magnum, RISCstation 2200)
	(Note nowadays QEMU supports Magnum 4000 with VXL)

    o	com_jazzio.c
	-   clock handling clean up (obtain from ARC BIOS)
	-   fifo disabling may be only needed on some Magnum?

    o	AD1848 audio support

    o	missing MI devices
		ses?, vcoda, ...


    o	Xserver

	-   VXL		Magnum, RISCstation 2200
	-   vga/S3	PICA, Image RISCstation - OpenBSD's?
	-   vga/cirrus	RISCserver 2200, Express5800/240 R4400 EISA
	-   vga/???	DESKstation Tyne, rPC44
	-   TGA		RISCstation 2250, Express5800/230 R4400 PCI
			(TGA support in XalphaNetBSD just works,
			 but needs XOrg'fy)

    o   Find out why bitmap load to S3-928 flashes screen. (X server)
	Know why (enable linear mode). Need S3 info.


    o	repair DescStation support
	-   requires bounce buffer bus_dma for Tyne
		XXX - too small bounce buffer size (128KB)

    o	Olivetti M700 support

    o	NEC Express5800/230 R10000 PCI (NEC-J95) support
	(needs info about interrupt, jazzio device address etc.)

    o	SNI RM200PCI/RM300/RM400/RM600 support
	(Linux/MIPS seems to have some info)


    o	parse ARC BIOS configuration information and use it

    o	fix kernel start address

    o	allocate PICA_TL_BASE dynamically

    o	remove inb/outb

    o	remove UADDR

    o	fix mem_clusters[] usage.

    o	intrcnt[] name cleanup, use MI evcnt(9)

    o	redesign interrupt handler framework.

    o	it is better to always disable the MIPS3 internal timer interrupts
	(i.e. MIPS_INT_MASK_5) if it is not needed for the system.
	those are the points which should be fixed:
	mips_idle: li t0, (MIPS_INT_MASK | MIPS_SR_INT_IE)
	machdep.c: curpcb->pcb_context[11] = MIPS_INT_MASK | MIPS_SR_INT_IE;
	spl0()
	splnone()

    o	XXX at least 2000/06/07 version is already quite unstable
	on PICA and NEC Image RISCstation. (but almost OK on Magnum)
	Userland commands dumps	core randomly.
	This version is before _MIPS_PADDR_T_64BIT changes
	and MIPS3_TLB_WIRED_UPAGES changes.	

	"vm_page_zero_enable = FALSE" makes this problem disappeared.
	(vm_page_zero_enable = FALSE by default on all archs w/ UBC, now)

	currently, page zero in the idle loop is also disabled on
	untested platforms like DESKstation rPC44/Tyne and SNI for safety.

	    XXX what's the current status of uvm_pageidlezero()?


    o	resolve "XXX"


(following entries might be MI MIPS items)

    o	Move the RO and WIRED attribute from the pte to the pv table.
	This saves four instructions in the tlb miss handler.

    o	clean up ALEAF/NLEAF/NON_LEAF/NNON_LEAF in userland.

Lots of other things.....