2022-09-25 18:44:52

by Amit Kumar Mahapatra

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Subject: [PATCH v3 0/7] spi: spi-zyqnmp-gqspi: Add tap delay and Versal platform support

- Fix kernel-doc warnings in GQSPI driver.
- Avoid setting CPOL, CPHA & baud rate multiple times.
- Add Versal platform support in GQSPI driver.
- Add tap delay support in GQSPI driver.
---
BRANCH: mtd/next

changes in v2:
- Used of_device_get_match_data( ) API to retrive match->data.
- Removed oneOf and used only enum.

changes in v3:
- Rearrange compatible strings in alphabetical order.
--
Amit Kumar Mahapatra (5):
spi: spi-zynqmp-gqspi: Fix kernel-doc warnings
spi: spi-zynqmp-gqspi: Set CPOL and CPHA during hardware init
spi: spi-zynqmp-gqspi: Avoid setting baud rate multiple times for same
SPI frequency
dt-bindings: spi: spi-zynqmp-qspi: Add support for Xilinx Versal QSPI
spi: spi-zynqmp-gqspi: Add tap delay support for GQSPI controller on
Versal platform

Naga Sureshkumar Relli (1):
spi: spi-zynqmp-gqspi: Add tap delay support for ZynqMP GQSPI
Controller

Rajan Vaja (1):
firmware: xilinx: Add qspi firmware interface

.../bindings/spi/spi-zynqmp-qspi.yaml | 4 +-
drivers/firmware/xilinx/zynqmp.c | 7 +
drivers/spi/spi-zynqmp-gqspi.c | 191 ++++++++++++++----
include/linux/firmware/xlnx-zynqmp.h | 19 ++
4 files changed, 184 insertions(+), 37 deletions(-)

--
2.17.1


2022-09-25 18:45:10

by Amit Kumar Mahapatra

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Subject: [PATCH v3 3/7] spi: spi-zynqmp-gqspi: Avoid setting baud rate multiple times for same SPI frequency

During every transfer the GQSPI driver configures the baud rate value. But
when there is no change in the SPI clock frequency the driver should avoid
rewriting the same baud rate value to the configuration register. Update
GQSPI driver to rewrite the baud rate value if there is any change in SPI
clock frequency.

Signed-off-by: Amit Kumar Mahapatra <[email protected]>
---
drivers/spi/spi-zynqmp-gqspi.c | 49 ++++++++++++++++++++++++----------
1 file changed, 35 insertions(+), 14 deletions(-)

diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c
index 1b56dd29057f..0fecea338027 100644
--- a/drivers/spi/spi-zynqmp-gqspi.c
+++ b/drivers/spi/spi-zynqmp-gqspi.c
@@ -159,6 +159,7 @@ enum mode_type {GQSPI_MODE_IO, GQSPI_MODE_DMA};
* @mode: Defines the mode in which QSPI is operating
* @data_completion: completion structure
* @op_lock: Operational lock
+ * @speed_hz: Current SPI bus clock speed in hz
*/
struct zynqmp_qspi {
struct spi_controller *ctlr;
@@ -179,6 +180,7 @@ struct zynqmp_qspi {
enum mode_type mode;
struct completion data_completion;
struct mutex op_lock;
+ u32 speed_hz;
};

/**
@@ -273,7 +275,8 @@ static void zynqmp_gqspi_selectslave(struct zynqmp_qspi *instanceptr,
*/
static void zynqmp_qspi_init_hw(struct zynqmp_qspi *xqspi)
{
- u32 config_reg;
+ u32 config_reg, baud_rate_val = 0;
+ ulong clk_rate;

/* Select the GQSPI mode */
zynqmp_gqspi_write(xqspi, GQSPI_SEL_OFST, GQSPI_SEL_MASK);
@@ -318,6 +321,16 @@ static void zynqmp_qspi_init_hw(struct zynqmp_qspi *xqspi)
else
config_reg &= ~GQSPI_CFG_CLK_POL_MASK;

+ /* Set the clock frequency */
+ clk_rate = clk_get_rate(xqspi->refclk);
+ while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
+ (clk_rate /
+ (GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) > xqspi->speed_hz)
+ baud_rate_val++;
+
+ config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
+ config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
+
zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);

/* Clear the TX and RX FIFO */
@@ -466,22 +479,29 @@ static int zynqmp_qspi_config_op(struct zynqmp_qspi *xqspi,
struct spi_device *qspi)
{
ulong clk_rate;
- u32 config_reg, baud_rate_val = 0;
+ u32 config_reg, req_speed_hz, baud_rate_val = 0;

- /* Set the clock frequency */
- /* If req_hz == 0, default to lowest speed */
- clk_rate = clk_get_rate(xqspi->refclk);
+ req_speed_hz = qspi->max_speed_hz;

- while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
- (clk_rate /
- (GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) > qspi->max_speed_hz)
- baud_rate_val++;
+ if (xqspi->speed_hz != req_speed_hz) {
+ xqspi->speed_hz = req_speed_hz;

- config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+ /* Set the clock frequency */
+ /* If req_speed_hz == 0, default to lowest speed */
+ clk_rate = clk_get_rate(xqspi->refclk);

- config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
- config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
- zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+ while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
+ (clk_rate /
+ (GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) >
+ req_speed_hz)
+ baud_rate_val++;
+
+ config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+
+ config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
+ config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
+ zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+ }
return 0;
}

@@ -1173,6 +1193,8 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)

ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
SPI_TX_DUAL | SPI_TX_QUAD;
+ ctlr->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
+ xqspi->speed_hz = ctlr->max_speed_hz;

/* QSPI controller initializations */
zynqmp_qspi_init_hw(xqspi);
@@ -1209,7 +1231,6 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
ctlr->mem_ops = &zynqmp_qspi_mem_ops;
ctlr->setup = zynqmp_qspi_setup_op;
- ctlr->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
ctlr->dev.of_node = np;
ctlr->auto_runtime_pm = true;
--
2.17.1

2022-09-25 19:14:27

by Amit Kumar Mahapatra

[permalink] [raw]
Subject: [PATCH v3 2/7] spi: spi-zynqmp-gqspi: Set CPOL and CPHA during hardware init

During every transfer GQSPI driver writes the CPOL & CPHA values to the
configuration register. But the CPOL & CPHA values do not change in between
multiple transfers, so moved the CPOL & CPHA initialization to hardware
init so that the values are written only once.

Signed-off-by: Amit Kumar Mahapatra <[email protected]>
---
drivers/spi/spi-zynqmp-gqspi.c | 32 +++++++++++++++++---------------
1 file changed, 17 insertions(+), 15 deletions(-)

diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c
index 973008a30a09..1b56dd29057f 100644
--- a/drivers/spi/spi-zynqmp-gqspi.c
+++ b/drivers/spi/spi-zynqmp-gqspi.c
@@ -266,7 +266,9 @@ static void zynqmp_gqspi_selectslave(struct zynqmp_qspi *instanceptr,
* - Enable manual slave select
* - Enable manual start
* - Deselect all the chip select lines
- * - Set the little endian mode of TX FIFO and
+ * - Set the little endian mode of TX FIFO
+ * - Set clock phase
+ * - Set clock polarity and
* - Enable the QSPI controller
*/
static void zynqmp_qspi_init_hw(struct zynqmp_qspi *xqspi)
@@ -305,10 +307,17 @@ static void zynqmp_qspi_init_hw(struct zynqmp_qspi *xqspi)
config_reg |= GQSPI_CFG_WP_HOLD_MASK;
/* Clear pre-scalar by default */
config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
- /* CPHA 0 */
- config_reg &= ~GQSPI_CFG_CLK_PHA_MASK;
- /* CPOL 0 */
- config_reg &= ~GQSPI_CFG_CLK_POL_MASK;
+ /* Set CPHA */
+ if (xqspi->ctlr->mode_bits & SPI_CPHA)
+ config_reg |= GQSPI_CFG_CLK_PHA_MASK;
+ else
+ config_reg &= ~GQSPI_CFG_CLK_PHA_MASK;
+ /* Set CPOL */
+ if (xqspi->ctlr->mode_bits & SPI_CPOL)
+ config_reg |= GQSPI_CFG_CLK_POL_MASK;
+ else
+ config_reg &= ~GQSPI_CFG_CLK_POL_MASK;
+
zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);

/* Clear the TX and RX FIFO */
@@ -470,14 +479,6 @@ static int zynqmp_qspi_config_op(struct zynqmp_qspi *xqspi,

config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);

- /* Set the QSPI clock phase and clock polarity */
- config_reg &= (~GQSPI_CFG_CLK_PHA_MASK) & (~GQSPI_CFG_CLK_POL_MASK);
-
- if (qspi->mode & SPI_CPHA)
- config_reg |= GQSPI_CFG_CLK_PHA_MASK;
- if (qspi->mode & SPI_CPOL)
- config_reg |= GQSPI_CFG_CLK_POL_MASK;
-
config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
@@ -1170,6 +1171,9 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
goto clk_dis_all;
}

+ ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
+ SPI_TX_DUAL | SPI_TX_QUAD;
+
/* QSPI controller initializations */
zynqmp_qspi_init_hw(xqspi);

@@ -1207,8 +1211,6 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
ctlr->setup = zynqmp_qspi_setup_op;
ctlr->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
- ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
- SPI_TX_DUAL | SPI_TX_QUAD;
ctlr->dev.of_node = np;
ctlr->auto_runtime_pm = true;

--
2.17.1

2022-09-26 05:35:53

by Mahapatra, Amit Kumar

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Subject: RE: [PATCH v3 0/7] spi: spi-zyqnmp-gqspi: Add tap delay and Versal platform support

Hello,

> -----Original Message-----
> From: Amit Kumar Mahapatra <[email protected]>
> Sent: Sunday, September 25, 2022 11:38 PM
> To: [email protected]; [email protected];
> [email protected]
> Cc: Mahapatra, Amit Kumar <[email protected]>; git (AMD-
> Xilinx) <[email protected]>; [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]; Mahapatra, Amit Kumar <amit.kumar-
> [email protected]>; Amit Kumar Mahapatra <amit.kumar-
> [email protected]>
> Subject: [PATCH v3 0/7] spi: spi-zyqnmp-gqspi: Add tap delay and Versal
> platform support

Please ignore this series, due to some issue at my end some of the patches in
this series could not be delivered. Once the issue is resolved I will resend this
series.

Regards,
Amit