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Subject[PATCH 1/8] MIPS: mm: XBurst CPU requires sync after DMA
Date
I am not sure why this is required, but if this is not enabled, reading
from a buffer in which data has been DMA'd may read incorrect values.

This used to happen for instance in mmc_app_send_scr()
(drivers/mmc/core/sd_ops.c), where data is DMA'd to a buffer then copied
by the CPU to a different location.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
---
arch/mips/Kconfig | 1 +
arch/mips/mm/dma-noncoherent.c | 1 +
2 files changed, 2 insertions(+)

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index ed51970c08e7..310ce50ad285 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -112,6 +112,7 @@ config MACH_INGENIC
select SYS_SUPPORTS_LITTLE_ENDIAN
select SYS_SUPPORTS_ZBOOT
select DMA_NONCOHERENT
+ select ARCH_HAS_SYNC_DMA_FOR_CPU
select IRQ_MIPS_CPU
select PINCTRL
select GPIOLIB
diff --git a/arch/mips/mm/dma-noncoherent.c b/arch/mips/mm/dma-noncoherent.c
index 212f3ce75a6b..3c4fc97b9f39 100644
--- a/arch/mips/mm/dma-noncoherent.c
+++ b/arch/mips/mm/dma-noncoherent.c
@@ -32,6 +32,7 @@ static inline bool cpu_needs_post_dma_flush(void)
case CPU_R12000:
case CPU_BMIPS5000:
case CPU_LOONGSON2EF:
+ case CPU_XBURST:
return true;
default:
/*
--
2.30.2
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