MIPS: Loongson64: Enable DMA noncoherent support

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@vger.kernel.org
Fixes: 71e2f4dd5a ("MIPS: Fork loongson2ef from loongson64")
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
This commit is contained in:
Jiaxun Yang 2023-11-07 11:15:19 +00:00 committed by Thomas Bogendoerfer
parent 8f7aa77a46
commit edc0378eee
3 changed files with 13 additions and 2 deletions

View File

@ -460,6 +460,7 @@ 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
@ -1251,6 +1252,7 @@ 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

View File

@ -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 {

View File

@ -13,6 +13,8 @@
* Copyright (C) 2009 Lemote Inc.
* Author: Wu Zhangjin, wuzhangjin@gmail.com
*/
#include <linux/dma-map-ops.h>
#include <linux/export.h>
#include <linux/pci_ids.h>
#include <asm/bootinfo.h>
@ -147,8 +149,14 @@ void __init prom_lefi_init_env(void)
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;