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authorAlexander Sverdlin <alexander.sverdlin@nokia.com>2019-03-19 18:18:07 +0100
committerMiquel Raynal <miquel.raynal@bootlin.com>2019-04-01 14:36:23 +0200
commit2b75ebeea6f4937d4d05ec4982c471cef9a29b7f (patch)
treec5cd30e3b77e5d96b0a125a6ca5979b015ad8691 /drivers/mtd
parentmtd: spi-nor: Fix comment of spi_nor_find_best_erase_type() (diff)
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mtd: spi-nor: intel-spi: Avoid crossing 4K address boundary on read/write
It was observed that reads crossing 4K address boundary are failing. This limitation is mentioned in Intel documents: Intel(R) 9 Series Chipset Family Platform Controller Hub (PCH) Datasheet: "5.26.3 Flash Access Program Register Access: * Program Register Accesses are not allowed to cross a 4 KB boundary..." Enhanced Serial Peripheral Interface (eSPI) Interface Base Specification (for Client and Server Platforms): "5.1.4 Address For other memory transactions, the address may start or end at any byte boundary. However, the address and payload length combination must not cross the naturally aligned address boundary of the corresponding Maximum Payload Size. It must not cross a 4 KB address boundary." Avoid this by splitting an operation crossing the boundary into two operations. Fixes: 8afda8b26d01 ("spi-nor: Add support for Intel SPI serial flash controller") Cc: stable@vger.kernel.org Reported-by: Romain Porte <romain.porte@nokia.com> Tested-by: Pascal Fabreges <pascal.fabreges@nokia.com> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Diffstat (limited to 'drivers/mtd')
-rw-r--r--drivers/mtd/spi-nor/intel-spi.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/mtd/spi-nor/intel-spi.c b/drivers/mtd/spi-nor/intel-spi.c
index af0a22019516..d60cbf23d9aa 100644
--- a/drivers/mtd/spi-nor/intel-spi.c
+++ b/drivers/mtd/spi-nor/intel-spi.c
@@ -632,6 +632,10 @@ static ssize_t intel_spi_read(struct spi_nor *nor, loff_t from, size_t len,
while (len > 0) {
block_size = min_t(size_t, len, INTEL_SPI_FIFO_SZ);
+ /* Read cannot cross 4K boundary */
+ block_size = min_t(loff_t, from + block_size,
+ round_up(from + 1, SZ_4K)) - from;
+
writel(from, ispi->base + FADDR);
val = readl(ispi->base + HSFSTS_CTL);
@@ -685,6 +689,10 @@ static ssize_t intel_spi_write(struct spi_nor *nor, loff_t to, size_t len,
while (len > 0) {
block_size = min_t(size_t, len, INTEL_SPI_FIFO_SZ);
+ /* Write cannot cross 4K boundary */
+ block_size = min_t(loff_t, to + block_size,
+ round_up(to + 1, SZ_4K)) - to;
+
writel(to, ispi->base + FADDR);
val = readl(ispi->base + HSFSTS_CTL);