Hi,
On Sat, Dec 30, 2023 at 11:16:41PM +0000, Jiaxun Yang wrote:
>
>
> 在2023年12月30日十二月 下午7:38，Salvatore Bonaccorso写道：
> > Hi,
> >
> > On Mon, Dec 11, 2023 at 07:22:24PM +0100, Greg Kroah-Hartman wrote:
> >> 5.10-stable review patch. If anyone has any objections, please let me know.
> >>
> >> ------------------
> >>
> >> From: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
> >>
> >> commit edc0378eee00200a5bedf1bb9f00ad390e0d1bd4 upstream.
> >>
> >> There are some Loongson64 systems come with broken coherent DMA
> >> support, firmware will set a bit in boot_param and pass nocoherentio
> >> in cmdline.
> >>
> >> However nonconherent support was missed out when spin off Loongson-2EF
> >> form Loongson64, and that boot_param change never made itself into
> >> upstream.
> >>
> >> Support DMA noncoherent properly to get those systems working.
> >>
> >> Cc: stable@xxxxxxxxxxxxxxx
> >> Fixes: 71e2f4dd5a65 ("MIPS: Fork loongson2ef from loongson64")
> >> Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
> >> Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> >> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> >> ---
> >> arch/mips/Kconfig | 2 ++
> >> arch/mips/include/asm/mach-loongson64/boot_param.h | 3 ++-
> >> arch/mips/loongson64/env.c | 10 +++++++++-
> >> 3 files changed, 13 insertions(+), 2 deletions(-)
> >>
> >> --- a/arch/mips/Kconfig
> >> +++ b/arch/mips/Kconfig
> >> @@ -468,6 +468,7 @@ config MACH_LOONGSON2EF
> >>
> >> config MACH_LOONGSON64
> >> bool "Loongson 64-bit family of machines"
> >> + select ARCH_DMA_DEFAULT_COHERENT
> >> select ARCH_SPARSEMEM_ENABLE
> >> select ARCH_MIGHT_HAVE_PC_PARPORT
> >> select ARCH_MIGHT_HAVE_PC_SERIO
> >> @@ -1379,6 +1380,7 @@ config CPU_LOONGSON64
> >> select CPU_SUPPORTS_MSA
> >> select CPU_DIEI_BROKEN if !LOONGSON3_ENHANCEMENT
> >> select CPU_MIPSR2_IRQ_VI
> >> + select DMA_NONCOHERENT
> >> select WEAK_ORDERING
> >> select WEAK_REORDERING_BEYOND_LLSC
> >> select MIPS_ASID_BITS_VARIABLE
> >> --- a/arch/mips/include/asm/mach-loongson64/boot_param.h
> >> +++ b/arch/mips/include/asm/mach-loongson64/boot_param.h
> >> @@ -117,7 +117,8 @@ struct irq_source_routing_table {
> >> u64 pci_io_start_addr;
> >> u64 pci_io_end_addr;
> >> u64 pci_config_addr;
> >> - u32 dma_mask_bits;
> >> + u16 dma_mask_bits;
> >> + u16 dma_noncoherent;
> >> } __packed;
> >>
> >> struct interface_info {
> >> --- a/arch/mips/loongson64/env.c
> >> +++ b/arch/mips/loongson64/env.c
> >> @@ -13,6 +13,8 @@
> >> * Copyright (C) 2009 Lemote Inc.
> >> * Author: Wu Zhangjin, wuzhangjin@xxxxxxxxx
> >> */
> >> +
> >> +#include <linux/dma-map-ops.h>
> >> #include <linux/export.h>
> >> #include <linux/pci_ids.h>
> >> #include <asm/bootinfo.h>
> >> @@ -131,8 +133,14 @@ void __init prom_init_env(void)
> >> loongson_sysconf.pci_io_base = eirq_source->pci_io_start_addr;
> >> loongson_sysconf.dma_mask_bits = eirq_source->dma_mask_bits;
> >> if (loongson_sysconf.dma_mask_bits < 32 ||
> >> - loongson_sysconf.dma_mask_bits > 64)
> >> + loongson_sysconf.dma_mask_bits > 64) {
> >> loongson_sysconf.dma_mask_bits = 32;
> >> + dma_default_coherent = true;
> >> + } else {
> >> + dma_default_coherent = !eirq_source->dma_noncoherent;
> >> + }
> >> +
> >> + pr_info("Firmware: Coherent DMA: %s\n", dma_default_coherent ? "on" : "off");
> >>
> >> loongson_sysconf.restart_addr = boot_p->reset_system.ResetWarm;
> >> loongson_sysconf.poweroff_addr = boot_p->reset_system.Shutdown;
> >
> > While preparing an update for Debian and finally building for all
> > supported architecture, the builds for mipsel and mips64el were
> > failing with:
> >
> > /<<PKGBUILDDIR>>/arch/mips/loongson64/env.c: In function
> > 'prom_init_env':
> > /<<PKGBUILDDIR>>/arch/mips/loongson64/env.c:138:3: error:
> > 'dma_default_coherent' undeclared (first use in this function); did you
> > mean 'dma_free_coherent'?
> > 138 | dma_default_coherent = true;
> > | ^~~~~~~~~~~~~~~~~~~~
> > | dma_free_coherent
> > /<<PKGBUILDDIR>>/arch/mips/loongson64/env.c:138:3: note: each
> > undeclared identifier is reported only once for each function it
> > appears in
> > make[6]: *** [/<<PKGBUILDDIR>>/scripts/Makefile.build:291:
> > arch/mips/loongson64/env.o] Error 1
> > make[6]: *** Waiting for unfinished jobs....
> >
> > Is here a prerequisite missing for the commit?
> >
> > Backporting though 6d4e9a8efe3d ("driver core: lift dma_default_coherent into
> > common code") which is from 5.12-rc1 though seems too intrusive, correct? Would
> > the alternative be to just revert the 3ee7e2faef87 ("MIPS: Loongson64: Enable
> > DMA noncoherent support") commit which landed in 5.10.204?
>
> Hi,
>
> Sorry for not spotting the issue in the first place.
>
> It actually requires more dependencies such as c00a60d6f4a1 ("of: address: always
> use dma_default_coherent for default coherency").
>
> I'll try to produce a backport series but better to drop this patch from stable
> for now.
Thanks a lot for your quick reply!
So I guess it only needs a revert for now from 5.10.y correct?
Greg, possible to already queue up the revert for 5.10.y for the next
upload?
Regards,
Salvatore
