On 11/1/23 2:39 PM, Jiaxun Yang wrote:
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 work.
Working.
Cc: stable@vger.kernel.org Fixes: 71e2f4dd5a65 ("MIPS: Fork loongson2ef from loongson64") Signed-off-by: Jiaxun Yang jiaxun.yang@flygoat.com
[...]
diff --git a/arch/mips/include/asm/mach-loongson64/boot_param.h b/arch/mips/include/asm/mach-loongson64/boot_param.h index 035b1a69e2d0..c454ef734c45 100644 --- 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 { diff --git a/arch/mips/loongson64/env.c b/arch/mips/loongson64/env.c index c961e2999f15..df0e92cd3920 100644 --- 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@gmail.com
*/
+#include <linux/dma-map-ops.h> #include <linux/export.h> #include <linux/pci_ids.h> #include <asm/bootinfo.h> @@ -147,8 +149,13 @@ 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) {
Please indent this line differently, so it doesn't blend with the following line (either start it in the same column as the *if* expression above, or add 1 more tab).
loongson_sysconf.dma_mask_bits = 32;
dma_default_coherent = true;- } else
The kernel style dictates that you need to add {} on the *else* branchh too.
dma_default_coherent = !eirq_source->dma_noncoherent;- pr_info("DMA coherent: %s\n", dma_default_coherent ? "on" : "off");
Maybe "Coherent DMA: %s\n"?
[...]
MBR, Sergey