diff options
| author | Raul E Rangel <rrangel@chromium.org> | 2021-07-12 14:19:43 -0600 |
|---|---|---|
| committer | Raul Rangel <rrangel@chromium.org> | 2021-07-18 15:15:15 +0000 |
| commit | 6f3c9018c6b830311db3a819706fc14954a5b0c2 (patch) | |
| tree | 54f17cc33574d329a6b1c6849e1a98510bf4ae14 /src | |
| parent | b29f9d471bade1cf6d5e0994af7ccf722ac65ef0 (diff) | |
soc/amd/common/block/lpc/spi_dma: Use mutex to protect DMA registers
Once we enable COOP_MULTITASKING, we need to guarantee that we don't
have multiple threads trying to access the DMA hardware.
BUG=b:179699789
TEST=Boot guybrush with APOB patches.
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: Ibb8e31c95d6722521425772f4210af45626c8e09
Reviewed-on: https://review.coreboot.org/c/coreboot/+/56231
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src')
| -rw-r--r-- | src/soc/amd/common/block/lpc/spi_dma.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/src/soc/amd/common/block/lpc/spi_dma.c b/src/soc/amd/common/block/lpc/spi_dma.c index b00b8ac511..fdc4f32593 100644 --- a/src/soc/amd/common/block/lpc/spi_dma.c +++ b/src/soc/amd/common/block/lpc/spi_dma.c @@ -13,6 +13,7 @@ #include <soc/pci_devs.h> #include <spi_flash.h> #include <string.h> +#include <thread.h> #include <types.h> /* The ROM is memory mapped just below 4GiB. Form a pointer for the base. */ @@ -164,6 +165,8 @@ static bool continue_spi_dma_transaction(const struct region_device *rd, return false; } +static struct thread_mutex spi_dma_hw_mutex; + static ssize_t spi_dma_readat_dma(const struct region_device *rd, void *destination, size_t source, size_t size) { @@ -177,12 +180,16 @@ static ssize_t spi_dma_readat_dma(const struct region_device *rd, void *destinat printk(BIOS_SPEW, "%s: start: dest: %p, source: %#zx, size: %zu\n", __func__, destination, source, size); + thread_mutex_lock(&spi_dma_hw_mutex); + start_spi_dma_transaction(&transaction); do { udelay(2); } while (continue_spi_dma_transaction(rd, &transaction)); + thread_mutex_unlock(&spi_dma_hw_mutex); + printk(BIOS_SPEW, "%s: end: dest: %p, source: %#zx, remaining: %zu\n", __func__, destination, source, transaction.remaining); |