summaryrefslogtreecommitdiff
path: root/src
diff options
context:
space:
mode:
authorFurquan Shaikh <furquan@chromium.org>2016-11-14 13:49:56 -0800
committerFurquan Shaikh <furquan@google.com>2016-11-15 22:21:07 +0100
commit0530b299212b4d584571ab588ad1d750ae57e251 (patch)
tree8a350ed7792b5ffb4a319a98a4483286074ac725 /src
parenta2f1d1892144b5e7b62055b1387553d839ad6ee8 (diff)
intel/apollolake: Ensure SPI operations do not cross 256-byte boundary
BIOS needs to ensure that SPI write does not cross 256-byte boundary. Else, if the write is across 256-byte boundary, then it corrupts the block by wrapping write to start of current block. Thus, ensure nuclear_spi_{read,write} operate within a single 256-byte block only at a time. BUG=chrome-os-partner:59813 BRANCH=None TEST=Verified that elog writes do not corrupt the event log when write is across 256-byte blocks. Change-Id: I854ca2979d65b9f1232f93182cb84d4dee4f4139 Signed-off-by: Furquan Shaikh <furquan@chromium.org> Reviewed-on: https://review.coreboot.org/17419 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Diffstat (limited to 'src')
-rw-r--r--src/soc/intel/apollolake/spi.c19
1 files changed, 17 insertions, 2 deletions
diff --git a/src/soc/intel/apollolake/spi.c b/src/soc/intel/apollolake/spi.c
index 8cb8aa5d6d..d60176a9aa 100644
--- a/src/soc/intel/apollolake/spi.c
+++ b/src/soc/intel/apollolake/spi.c
@@ -259,6 +259,21 @@ static int nuclear_spi_erase(struct spi_flash *flash, uint32_t offset, size_t le
return SUCCESS;
}
+/*
+ * Ensure read/write xfer len is not greater than SPIBAR_FDATA_FIFO_SIZE and
+ * that the operation does not cross 256-byte boundary.
+ */
+static size_t get_xfer_len(uint32_t addr, size_t len)
+{
+ size_t xfer_len = min(len, SPIBAR_FDATA_FIFO_SIZE);
+ size_t bytes_left = ALIGN_UP(addr, 256) - addr;
+
+ if (bytes_left)
+ xfer_len = min(xfer_len, bytes_left);
+
+ return xfer_len;
+}
+
static int nuclear_spi_read(struct spi_flash *flash, uint32_t addr, size_t len, void *buf)
{
int ret;
@@ -268,7 +283,7 @@ static int nuclear_spi_read(struct spi_flash *flash, uint32_t addr, size_t len,
BOILERPLATE_CREATE_CTX(ctx);
while (len) {
- xfer_len = min(len, SPIBAR_FDATA_FIFO_SIZE);
+ xfer_len = get_xfer_len(addr, len);
ret = exec_sync_hwseq_xfer(ctx, SPIBAR_HSFSTS_CYCLE_READ,
addr, xfer_len);
@@ -295,7 +310,7 @@ static int nuclear_spi_write(struct spi_flash *flash,
BOILERPLATE_CREATE_CTX(ctx);
while (len) {
- xfer_len = min(len, SPIBAR_FDATA_FIFO_SIZE);
+ xfer_len = get_xfer_len(addr, len);
fill_xfer_fifo(ctx, data, xfer_len);
ret = exec_sync_hwseq_xfer(ctx, SPIBAR_HSFSTS_CYCLE_WRITE,