2018-04-26 18:49:55

by Kamal Dasu

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Subject: [PATCH v2 0/2] spi: bcm-qspi: Fix spi-nor chip select logic for BSPI

When using the spi-nor master controller always verify the chip select
bit in the cs register. Also do not use CDRAM PCS bit in BSPI mode.
Additionally make sure to enable/disable BSPI_MAST_N_BOOT_CTRL while using
BSPI mode.

V2 changes:
- Added "Fixes:" tag to 1/2 and 2/2 patches

Kamal Dasu (2):
spi: bcm-qspi: Avoid setting MSPI_CDRAM_PCS for spi-nor master
spi: bcm-qspi: Always read and set BSPI_MAST_N_BOOT_CTRL

drivers/spi/spi-bcm-qspi.c | 28 ++++++++++++++++++----------
1 file changed, 18 insertions(+), 10 deletions(-)

--
2.7.4



2018-04-26 18:49:57

by Kamal Dasu

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Subject: [PATCH v2 1/2] spi: bcm-qspi: Avoid setting MSPI_CDRAM_PCS for spi-nor master

Added fix for probing of spi-nor device non-zero chip selects. Set
MSPI_CDRAM_PCS (peripheral chip select) with spi master for MSPI
controller and not for MSPI/BSPI spi-nor master controller. Ensure
setting of cs bit in chip select register on chip select change.

Fixes: fa236a7ef24048 ("spi: bcm-qspi: Add Broadcom MSPI driver")
Signed-off-by: Kamal Dasu <[email protected]>
---
drivers/spi/spi-bcm-qspi.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c
index 1596d35..2946989 100644
--- a/drivers/spi/spi-bcm-qspi.c
+++ b/drivers/spi/spi-bcm-qspi.c
@@ -519,16 +519,19 @@ static void bcm_qspi_disable_bspi(struct bcm_qspi *qspi)

static void bcm_qspi_chip_select(struct bcm_qspi *qspi, int cs)
{
- u32 data = 0;
+ u32 rd = 0;
+ u32 wr = 0;

- if (qspi->curr_cs == cs)
- return;
if (qspi->base[CHIP_SELECT]) {
- data = bcm_qspi_read(qspi, CHIP_SELECT, 0);
- data = (data & ~0xff) | (1 << cs);
- bcm_qspi_write(qspi, CHIP_SELECT, 0, data);
+ rd = bcm_qspi_read(qspi, CHIP_SELECT, 0);
+ wr = (rd & ~0xff) | (1 << cs);
+ if (rd == wr)
+ return;
+ bcm_qspi_write(qspi, CHIP_SELECT, 0, wr);
usleep_range(10, 20);
}
+
+ dev_dbg(&qspi->pdev->dev, "using cs:%d\n", cs);
qspi->curr_cs = cs;
}

@@ -755,8 +758,13 @@ static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spi)
dev_dbg(&qspi->pdev->dev, "WR %04x\n", val);
}
mspi_cdram = MSPI_CDRAM_CONT_BIT;
- mspi_cdram |= (~(1 << spi->chip_select) &
- MSPI_CDRAM_PCS);
+
+ if (has_bspi(qspi))
+ mspi_cdram &= ~1;
+ else
+ mspi_cdram |= (~(1 << spi->chip_select) &
+ MSPI_CDRAM_PCS);
+
mspi_cdram |= ((tp.trans->bits_per_word <= 8) ? 0 :
MSPI_CDRAM_BITSE_BIT);

--
2.7.4


2018-04-26 18:50:09

by Kamal Dasu

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Subject: [PATCH v2 2/2] spi: bcm-qspi: Always read and set BSPI_MAST_N_BOOT_CTRL

Always confirm the BSPI_MAST_N_BOOT_CTRL bit when enabling
or disabling BSPI transfers.

Fixes: 4e3b2d236fe00 ("spi: bcm-qspi: Add BSPI spi-nor flash controller driver")
Signed-off-by: Kamal Dasu <[email protected]>
---
drivers/spi/spi-bcm-qspi.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c
index 2946989..6573152 100644
--- a/drivers/spi/spi-bcm-qspi.c
+++ b/drivers/spi/spi-bcm-qspi.c
@@ -490,7 +490,7 @@ static int bcm_qspi_bspi_set_mode(struct bcm_qspi *qspi,

static void bcm_qspi_enable_bspi(struct bcm_qspi *qspi)
{
- if (!has_bspi(qspi) || (qspi->bspi_enabled))
+ if (!has_bspi(qspi))
return;

qspi->bspi_enabled = 1;
@@ -505,7 +505,7 @@ static void bcm_qspi_enable_bspi(struct bcm_qspi *qspi)

static void bcm_qspi_disable_bspi(struct bcm_qspi *qspi)
{
- if (!has_bspi(qspi) || (!qspi->bspi_enabled))
+ if (!has_bspi(qspi))
return;

qspi->bspi_enabled = 0;
--
2.7.4