Message ID | 20190226112334.401-1-alexander.sverdlin@nokia.com |
---|---|
State | Changes Requested |
Headers | show |
Series | spi-nor: intel-spi: Avoid crossing 4K address boundary on read/write | expand |
On Tue, Feb 26, 2019 at 11:23:49AM +0000, Sverdlin, Alexander (Nokia - DE/Ulm) wrote: > 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. > > 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> > --- > drivers/mtd/spi-nor/intel-spi.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/mtd/spi-nor/intel-spi.c b/drivers/mtd/spi-nor/intel-spi.c > index af0a220..b83ea79 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 */ > + if ((from ^ (from + block_size - 1)) & ~(SZ_4K - 1LL)) Don't we have existing macros in kernel.h that can be used here and below? > + block_size -= (from + block_size) & (SZ_4K - 1); > + > 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 */ > + if ((to ^ (to + block_size - 1)) & ~(SZ_4K - 1LL)) > + block_size -= (to + block_size) & (SZ_4K - 1); > + > writel(to, ispi->base + FADDR); > > val = readl(ispi->base + HSFSTS_CTL); > -- > 2.4.6
Hi, [This is an automated email] This commit has been processed because it contains a -stable tag. The stable tag indicates that it's relevant for the following trees: all The bot has tested the following trees: v4.20.12, v4.19.25, v4.14.103, v4.9.160, v4.4.176, v3.18.136. v4.20.12: Build OK! v4.19.25: Build OK! v4.14.103: Build OK! v4.9.160: Failed to apply! Possible dependencies: 8afda8b26d01 ("spi-nor: Add support for Intel SPI serial flash controller") v4.4.176: Failed to apply! Possible dependencies: 8afda8b26d01 ("spi-nor: Add support for Intel SPI serial flash controller") v3.18.136: Failed to apply! Possible dependencies: 8afda8b26d01 ("spi-nor: Add support for Intel SPI serial flash controller") f617b9587c16 ("mtd: spi-nor: add driver for NXP SPI Flash Interface (SPIFI)") How should we proceed with this patch? -- Thanks, Sasha
diff --git a/drivers/mtd/spi-nor/intel-spi.c b/drivers/mtd/spi-nor/intel-spi.c index af0a220..b83ea79 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 */ + if ((from ^ (from + block_size - 1)) & ~(SZ_4K - 1LL)) + block_size -= (from + block_size) & (SZ_4K - 1); + 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 */ + if ((to ^ (to + block_size - 1)) & ~(SZ_4K - 1LL)) + block_size -= (to + block_size) & (SZ_4K - 1); + writel(to, ispi->base + FADDR); val = readl(ispi->base + HSFSTS_CTL);