* [PATCH 1/3] mtd: spi-nor: stm32-quadspi: Fix uninitialized error return code
2017-10-26 11:54 [PATCH 0/3] mtd: spi-nor: stm32-quadspi: fixes Ludovic Barre
@ 2017-10-26 11:54 ` Ludovic Barre
2017-10-26 11:54 ` [PATCH 2/3] mtd: spi-nor: stm32-quadspi: fix prefetching outside fsize Ludovic Barre
[not found] ` <1509018894-15111-1-git-send-email-ludovic.Barre-qxv4g6HH51o@public.gmane.org>
2 siblings, 0 replies; 4+ messages in thread
From: Ludovic Barre @ 2017-10-26 11:54 UTC (permalink / raw)
To: Cyrille Pitchen, Marek Vasut
Cc: David Woodhouse, Brian Norris, Boris Brezillon,
Richard Weinberger, Alexandre Torgue, Rob Herring, linux-mtd,
linux-kernel, devicetree, linux-arm-kernel, Geert Uytterhoeven,
Ludovic Barre
From: Geert Uytterhoeven <geert@linux-m68k.org>
With gcc 4.1.2:
drivers/mtd/spi-nor/stm32-quadspi.c: In function ‘stm32_qspi_tx_poll’:
drivers/mtd/spi-nor/stm32-quadspi.c:230: warning: ‘ret’ may be used uninitialized in this function
Indeed, if stm32_qspi_cmd.len is zero, ret will be uninitialized.
This length is passed from outside the driver using the
spi_nor.{read,write}{,_reg}() callbacks.
Several functions in drivers/mtd/spi-nor/spi-nor.c (e.g. write_enable(),
write_disable(), and erase_chip()) call spi_nor.write_reg() with a zero
length.
Fix this by returning an explicit zero on success.
Fixes: 0d43d7ab277a048c ("mtd: spi-nor: add driver for STM32 quad spi flash controller")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
---
drivers/mtd/spi-nor/stm32-quadspi.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/mtd/spi-nor/stm32-quadspi.c b/drivers/mtd/spi-nor/stm32-quadspi.c
index 86c0931..ad6a3e1 100644
--- a/drivers/mtd/spi-nor/stm32-quadspi.c
+++ b/drivers/mtd/spi-nor/stm32-quadspi.c
@@ -240,12 +240,12 @@ static int stm32_qspi_tx_poll(struct stm32_qspi *qspi,
STM32_QSPI_FIFO_TIMEOUT_US);
if (ret) {
dev_err(qspi->dev, "fifo timeout (stat:%#x)\n", sr);
- break;
+ return ret;
}
tx_fifo(buf++, qspi->io_base + QUADSPI_DR);
}
- return ret;
+ return 0;
}
static int stm32_qspi_tx_mm(struct stm32_qspi *qspi,
--
2.7.4
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH 2/3] mtd: spi-nor: stm32-quadspi: fix prefetching outside fsize
2017-10-26 11:54 [PATCH 0/3] mtd: spi-nor: stm32-quadspi: fixes Ludovic Barre
2017-10-26 11:54 ` [PATCH 1/3] mtd: spi-nor: stm32-quadspi: Fix uninitialized error return code Ludovic Barre
@ 2017-10-26 11:54 ` Ludovic Barre
[not found] ` <1509018894-15111-1-git-send-email-ludovic.Barre-qxv4g6HH51o@public.gmane.org>
2 siblings, 0 replies; 4+ messages in thread
From: Ludovic Barre @ 2017-10-26 11:54 UTC (permalink / raw)
To: Cyrille Pitchen, Marek Vasut
Cc: David Woodhouse, Brian Norris, Boris Brezillon,
Richard Weinberger, Alexandre Torgue, Rob Herring, linux-mtd,
linux-kernel, devicetree, linux-arm-kernel, Ludovic Barre
From: Ludovic Barre <ludovic.barre@st.com>
When memory-mapped mode is used, a prefetching mechanism fully
managed by the hardware allows to optimize the read from external
the QSPI memory. A 32-bytes FIFO is used for prefetching.
When the limit of flash size - fifo size is reached the prefetching
mechanism tries to read outside the fsize.
The stm32 quadspi hardware become busy and should be aborted.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Reported-by: Bruno Herrera <bruherrera@gmail.com>
Tested-by: Bruno Herrera <bruherrera@gmail.com>
---
drivers/mtd/spi-nor/stm32-quadspi.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/mtd/spi-nor/stm32-quadspi.c b/drivers/mtd/spi-nor/stm32-quadspi.c
index ad6a3e1..70710be 100644
--- a/drivers/mtd/spi-nor/stm32-quadspi.c
+++ b/drivers/mtd/spi-nor/stm32-quadspi.c
@@ -113,6 +113,7 @@
#define STM32_MAX_MMAP_SZ SZ_256M
#define STM32_MAX_NORCHIP 2
+#define STM32_QSPI_FIFO_SZ 32
#define STM32_QSPI_FIFO_TIMEOUT_US 30000
#define STM32_QSPI_BUSY_TIMEOUT_US 100000
@@ -124,6 +125,7 @@ struct stm32_qspi_flash {
u32 presc;
u32 read_mode;
bool registered;
+ u32 prefetch_limit;
};
struct stm32_qspi {
@@ -272,6 +274,7 @@ static int stm32_qspi_send(struct stm32_qspi_flash *flash,
{
struct stm32_qspi *qspi = flash->qspi;
u32 ccr, dcr, cr;
+ u32 last_byte;
int err;
err = stm32_qspi_wait_nobusy(qspi);
@@ -314,6 +317,10 @@ static int stm32_qspi_send(struct stm32_qspi_flash *flash,
if (err)
goto abort;
writel_relaxed(FCR_CTCF, qspi->io_base + QUADSPI_FCR);
+ } else {
+ last_byte = cmd->addr + cmd->len;
+ if (last_byte > flash->prefetch_limit)
+ goto abort;
}
return err;
@@ -322,7 +329,9 @@ static int stm32_qspi_send(struct stm32_qspi_flash *flash,
cr = readl_relaxed(qspi->io_base + QUADSPI_CR) | CR_ABORT;
writel_relaxed(cr, qspi->io_base + QUADSPI_CR);
- dev_err(qspi->dev, "%s abort err:%d\n", __func__, err);
+ if (err)
+ dev_err(qspi->dev, "%s abort err:%d\n", __func__, err);
+
return err;
}
@@ -550,6 +559,7 @@ static int stm32_qspi_flash_setup(struct stm32_qspi *qspi,
}
flash->fsize = FSIZE_VAL(mtd->size);
+ flash->prefetch_limit = mtd->size - STM32_QSPI_FIFO_SZ;
flash->read_mode = CCR_FMODE_MM;
if (mtd->size > qspi->mm_size)
--
2.7.4
^ permalink raw reply related [flat|nested] 4+ messages in thread