[U-Boot] [PATCH resend] spi/arm-pl022: Add support for ARM PL022 spi controller
From: Armando Visconti armando.visconti@st.com
This patch adds the support for the ARM PL022 SPI controller for the standard variant (0x00041022), which has a 16bit wide and 8 locations deep TX/RX FIFO.
Signed-off-by: Armando Visconti armando.visconti@st.com Signed-off-by: Vipin Kumar vipin.kumar@st.com ---
Dear Wolfgang, Stefan,
There seems to be no direct owner of spi framework. So, I am directing this patch to you
Regards Vipin
drivers/spi/Makefile | 1 + drivers/spi/pl022_spi.c | 308 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 309 insertions(+) create mode 100644 drivers/spi/pl022_spi.c
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 824d357..3a4e4b0 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -42,6 +42,7 @@ COBJS-$(CONFIG_MXC_SPI) += mxc_spi.o COBJS-$(CONFIG_MXS_SPI) += mxs_spi.o COBJS-$(CONFIG_OC_TINY_SPI) += oc_tiny_spi.o COBJS-$(CONFIG_OMAP3_SPI) += omap3_spi.o +COBJS-$(CONFIG_PL022_SPI) += pl022_spi.o COBJS-$(CONFIG_SOFT_SPI) += soft_spi.o COBJS-$(CONFIG_SH_SPI) += sh_spi.o COBJS-$(CONFIG_FSL_ESPI) += fsl_espi.o diff --git a/drivers/spi/pl022_spi.c b/drivers/spi/pl022_spi.c new file mode 100644 index 0000000..3ea769a --- /dev/null +++ b/drivers/spi/pl022_spi.c @@ -0,0 +1,308 @@ +/* + * (C) Copyright 2012 + * Armando Visconti, ST Microelectronics, armando.visconti@st.com. + * + * Driver for ARM PL022 SPI Controller. Based on atmel_spi.c + * by Atmel Corporation. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <malloc.h> +#include <spi.h> +#include <asm/io.h> +#include <asm/arch/hardware.h> + +/* SSP registers mapping */ +#define SSP_CR0 0x000 +#define SSP_CR1 0x004 +#define SSP_DR 0x008 +#define SSP_SR 0x00C +#define SSP_CPSR 0x010 +#define SSP_IMSC 0x014 +#define SSP_RIS 0x018 +#define SSP_MIS 0x01C +#define SSP_ICR 0x020 +#define SSP_DMACR 0x024 +#define SSP_ITCR 0x080 +#define SSP_ITIP 0x084 +#define SSP_ITOP 0x088 +#define SSP_TDR 0x08C + +#define SSP_PID0 0xFE0 +#define SSP_PID1 0xFE4 +#define SSP_PID2 0xFE8 +#define SSP_PID3 0xFEC + +#define SSP_CID0 0xFF0 +#define SSP_CID1 0xFF4 +#define SSP_CID2 0xFF8 +#define SSP_CID3 0xFFC + +/* SSP Control Register 0 - SSP_CR0 */ +#define SSP_CR0_SPO (0x1 << 6) +#define SSP_CR0_SPH (0x1 << 7) +#define SSP_CR0_8BIT_MODE (0x07) +#define SSP_SCR_MAX (0xFF) +#define SSP_SCR_SHFT 8 + +/* SSP Control Register 0 - SSP_CR1 */ +#define SSP_CR1_MASK_SSE (0x1 << 1) + +#define SSP_CPSR_MAX (0xFE) + +/* SSP Status Register - SSP_SR */ +#define SSP_SR_MASK_TFE (0x1 << 0) /* Transmit FIFO empty */ +#define SSP_SR_MASK_TNF (0x1 << 1) /* Transmit FIFO not full */ +#define SSP_SR_MASK_RNE (0x1 << 2) /* Receive FIFO not empty */ +#define SSP_SR_MASK_RFF (0x1 << 3) /* Receive FIFO full */ +#define SSP_SR_MASK_BSY (0x1 << 4) /* Busy Flag */ + +struct pl022_spi_slave { + struct spi_slave slave; + void *regs; + unsigned int freq; +}; + +static inline struct pl022_spi_slave *to_pl022_spi(struct spi_slave *slave) +{ + return container_of(slave, struct pl022_spi_slave, slave); +} + +/* + * Following three functions should be provided by the + * board support package. + */ +int spi_cs_is_valid(unsigned int bus, unsigned int cs) + __attribute__((weak, alias("__spi_cs_is_valid"))); +void spi_cs_activate(struct spi_slave *slave) + __attribute__((weak, alias("__spi_cs_activate"))); +void spi_cs_deactivate(struct spi_slave *slave) + __attribute__((weak, alias("__spi_cs_deactivate"))); + +int __spi_cs_is_valid(unsigned int bus, unsigned int cs) +{ + return 1; +} + +void __spi_cs_activate(struct spi_slave *slave) +{ + /* do nothing */ +} + +void __spi_cs_deactivate(struct spi_slave *slave) +{ + /* do nothing */ +} + +void spi_init() +{ + /* do nothing */ +} + +/* + * ARM PL022 exists in different 'flavors'. + * This drivers currently support the standard variant (0x00041022), that has a + * 16bit wide and 8 locations deep TX/RX FIFO. + */ +static int pl022_is_supported(struct pl022_spi_slave *ps) +{ + /* PL022 version is 0x00041022 */ + if ((readw(ps->regs + SSP_PID0) == 0x22) && + (readw(ps->regs + SSP_PID1) == 0x10) && + ((readw(ps->regs + SSP_PID2) & 0xf) == 0x04) && + (readw(ps->regs + SSP_PID3) == 0x00)) + return 1; + + return 0; +} + +struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, + unsigned int max_hz, unsigned int mode) +{ + struct pl022_spi_slave *ps; + u16 scr = 1, prescaler, cr0 = 0, cpsr = 0; + + if (!spi_cs_is_valid(bus, cs)) + return NULL; + + ps = malloc(sizeof(*ps)); + if (!ps) + return NULL; + + ps->slave.bus = bus; + ps->slave.cs = cs; + ps->freq = max_hz; + + switch (bus) { + case 0: + ps->regs = (void *)CONFIG_SYS_SPI_BASE; + break; +#ifdef CONFIG_SYS_SPI_BASE1 + case 1: + ps->regs = (void *)CONFIG_SYS_SPI_BASE1; + break; +#endif +#ifdef CONFIG_SYS_SPI_BASE2 + case 2: + ps->regs = (void *)CONFIG_SYS_SPI_BASE2; + break; +#endif +#ifdef CONFIG_SYS_SPI_BASE3 + case 3: + ps->regs = (void *)CONFIG_SYS_SPI_BASE3; + break; +#endif + default: + free(ps); + return NULL; + } + + /* Check the PL022 version */ + if (!pl022_is_supported(ps)) { + free(ps); + return NULL; + } + + /* Set requested polarity and 8bit mode */ + cr0 = SSP_CR0_8BIT_MODE; + cr0 |= (mode & SPI_CPHA) ? SSP_CR0_SPH : 0; + cr0 |= (mode & SPI_CPOL) ? SSP_CR0_SPO : 0; + + writew(cr0, ps->regs + SSP_CR0); + + /* Program the SSPClk frequency */ + prescaler = CONFIG_SYS_SPI_CLK / ps->freq; + + if (prescaler <= 0xFF) + cpsr = prescaler; + else { + for (scr = 1; scr <= SSP_SCR_MAX; scr++) { + if (!(prescaler % scr)) { + cpsr = prescaler / scr; + if (cpsr <= SSP_CPSR_MAX) + break; + } + } + + if (scr > SSP_SCR_MAX) { + scr = SSP_SCR_MAX; + cpsr = prescaler / scr; + cpsr &= SSP_CPSR_MAX; + } + } + + if (cpsr & 0x1) + cpsr++; + + writew(cpsr, ps->regs + SSP_CPSR); + cr0 = readw(ps->regs + SSP_CR0); + writew(cr0 | (scr - 1) << SSP_SCR_SHFT, ps->regs + SSP_CR0); + + return &ps->slave; +} + +void spi_free_slave(struct spi_slave *slave) +{ + struct pl022_spi_slave *ps = to_pl022_spi(slave); + + free(ps); +} + +int spi_claim_bus(struct spi_slave *slave) +{ + struct pl022_spi_slave *ps = to_pl022_spi(slave); + + /* Enable the SPI hardware */ + writew(readw(ps->regs + SSP_CR1) | SSP_CR1_MASK_SSE, + ps->regs + SSP_CR1); + + return 0; +} + +void spi_release_bus(struct spi_slave *slave) +{ + struct pl022_spi_slave *ps = to_pl022_spi(slave); + + /* Disable the SPI hardware */ + writew(0x0, ps->regs + SSP_CR1); +} + +int spi_xfer(struct spi_slave *slave, unsigned int bitlen, + const void *dout, void *din, unsigned long flags) +{ + struct pl022_spi_slave *ps = to_pl022_spi(slave); + u32 len_tx = 0, len_rx = 0, len; + u32 ret = 0; + const u8 *txp = dout; + u8 *rxp = din, value; + + if (bitlen == 0) + /* Finish any previously submitted transfers */ + goto out; + + /* + * TODO: The controller can do non-multiple-of-8 bit + * transfers, but this driver currently doesn't support it. + * + * It's also not clear how such transfers are supposed to be + * represented as a stream of bytes...this is a limitation of + * the current SPI interface. + */ + if (bitlen % 8) { + ret = -1; + + /* Errors always terminate an ongoing transfer */ + flags |= SPI_XFER_END; + goto out; + } + + len = bitlen / 8; + + if (flags & SPI_XFER_BEGIN) + spi_cs_activate(slave); + + while (len_tx < len) { + if (readw(ps->regs + SSP_SR) & SSP_SR_MASK_TNF) { + value = (txp != NULL) ? *txp++ : 0; + writew(value, ps->regs + SSP_DR); + len_tx++; + } + + if (readw(ps->regs + SSP_SR) & SSP_SR_MASK_RNE) { + value = readw(ps->regs + SSP_DR); + if (rxp) + *rxp++ = value; + len_rx++; + } + } + + while (len_rx < len_tx) { + if (readw(ps->regs + SSP_SR) & SSP_SR_MASK_RNE) { + value = readw(ps->regs + SSP_DR); + if (rxp) + *rxp++ = value; + len_rx++; + } + } + +out: + if (flags & SPI_XFER_END) + spi_cs_deactivate(slave); + + return ret; +}
(Added Mike to Cc)
On 12/06/2012 07:56 AM, Vipin Kumar wrote:
From: Armando Visconti armando.visconti@st.com
This patch adds the support for the ARM PL022 SPI controller for the standard variant (0x00041022), which has a 16bit wide and 8 locations deep TX/RX FIFO.
Signed-off-by: Armando Visconti armando.visconti@st.com Signed-off-by: Vipin Kumar vipin.kumar@st.com
Dear Wolfgang, Stefan,
There seems to be no direct owner of spi framework. So, I am directing this patch to you
IIRC, Mike Frysinger did a bit of SPI maintenance in the last years. Perhaps he can comment. Mike, still around?
Thanks, Stefan
Ping. Can I get a few Reviewed-by's :)
On 12/6/2012 1:35 PM, Stefan Roese wrote:
(Added Mike to Cc)
On 12/06/2012 07:56 AM, Vipin Kumar wrote:
From: Armando Viscontiarmando.visconti@st.com
This patch adds the support for the ARM PL022 SPI controller for the standard variant (0x00041022), which has a 16bit wide and 8 locations deep TX/RX FIFO.
Signed-off-by: Armando Viscontiarmando.visconti@st.com Signed-off-by: Vipin Kumarvipin.kumar@st.com
Dear Wolfgang, Stefan,
There seems to be no direct owner of spi framework. So, I am directing this patch to you
IIRC, Mike Frysinger did a bit of SPI maintenance in the last years. Perhaps he can comment. Mike, still around?
Thanks, Stefan
On 12/06/2012 07:56 AM, Vipin Kumar wrote:
From: Armando Visconti armando.visconti@st.com
This patch adds the support for the ARM PL022 SPI controller for the standard variant (0x00041022), which has a 16bit wide and 8 locations deep TX/RX FIFO.
Signed-off-by: Armando Visconti armando.visconti@st.com Signed-off-by: Vipin Kumar vipin.kumar@st.com
Dear Wolfgang, Stefan,
There seems to be no direct owner of spi framework. So, I am directing this patch to you
A few comments below.
Regards Vipin
drivers/spi/Makefile | 1 + drivers/spi/pl022_spi.c | 308 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 309 insertions(+) create mode 100644 drivers/spi/pl022_spi.c
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 824d357..3a4e4b0 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -42,6 +42,7 @@ COBJS-$(CONFIG_MXC_SPI) += mxc_spi.o COBJS-$(CONFIG_MXS_SPI) += mxs_spi.o COBJS-$(CONFIG_OC_TINY_SPI) += oc_tiny_spi.o COBJS-$(CONFIG_OMAP3_SPI) += omap3_spi.o +COBJS-$(CONFIG_PL022_SPI) += pl022_spi.o COBJS-$(CONFIG_SOFT_SPI) += soft_spi.o COBJS-$(CONFIG_SH_SPI) += sh_spi.o COBJS-$(CONFIG_FSL_ESPI) += fsl_espi.o diff --git a/drivers/spi/pl022_spi.c b/drivers/spi/pl022_spi.c new file mode 100644 index 0000000..3ea769a --- /dev/null +++ b/drivers/spi/pl022_spi.c @@ -0,0 +1,308 @@ +/*
- (C) Copyright 2012
- Armando Visconti, ST Microelectronics, armando.visconti@st.com.
- Driver for ARM PL022 SPI Controller. Based on atmel_spi.c
- by Atmel Corporation.
- This program is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2 of
- the License, or (at your option) any later version.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- MA 02111-1307 USA
- */
+#include <common.h> +#include <malloc.h> +#include <spi.h> +#include <asm/io.h> +#include <asm/arch/hardware.h>
+/* SSP registers mapping */ +#define SSP_CR0 0x000 +#define SSP_CR1 0x004 +#define SSP_DR 0x008 +#define SSP_SR 0x00C +#define SSP_CPSR 0x010 +#define SSP_IMSC 0x014 +#define SSP_RIS 0x018 +#define SSP_MIS 0x01C +#define SSP_ICR 0x020 +#define SSP_DMACR 0x024 +#define SSP_ITCR 0x080 +#define SSP_ITIP 0x084 +#define SSP_ITOP 0x088 +#define SSP_TDR 0x08C
Please use C-structs instead to access the registers.
+#define SSP_PID0 0xFE0 +#define SSP_PID1 0xFE4 +#define SSP_PID2 0xFE8 +#define SSP_PID3 0xFEC
+#define SSP_CID0 0xFF0 +#define SSP_CID1 0xFF4 +#define SSP_CID2 0xFF8 +#define SSP_CID3 0xFFC
+/* SSP Control Register 0 - SSP_CR0 */ +#define SSP_CR0_SPO (0x1 << 6) +#define SSP_CR0_SPH (0x1 << 7) +#define SSP_CR0_8BIT_MODE (0x07) +#define SSP_SCR_MAX (0xFF) +#define SSP_SCR_SHFT 8
+/* SSP Control Register 0 - SSP_CR1 */ +#define SSP_CR1_MASK_SSE (0x1 << 1)
+#define SSP_CPSR_MAX (0xFE)
+/* SSP Status Register - SSP_SR */ +#define SSP_SR_MASK_TFE (0x1 << 0) /* Transmit FIFO empty */ +#define SSP_SR_MASK_TNF (0x1 << 1) /* Transmit FIFO not full */ +#define SSP_SR_MASK_RNE (0x1 << 2) /* Receive FIFO not empty */ +#define SSP_SR_MASK_RFF (0x1 << 3) /* Receive FIFO full */ +#define SSP_SR_MASK_BSY (0x1 << 4) /* Busy Flag */
+struct pl022_spi_slave {
- struct spi_slave slave;
- void *regs;
- unsigned int freq;
+};
+static inline struct pl022_spi_slave *to_pl022_spi(struct spi_slave *slave) +{
- return container_of(slave, struct pl022_spi_slave, slave);
+}
+/*
- Following three functions should be provided by the
- board support package.
- */
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
- __attribute__((weak, alias("__spi_cs_is_valid")));
+void spi_cs_activate(struct spi_slave *slave)
- __attribute__((weak, alias("__spi_cs_activate")));
+void spi_cs_deactivate(struct spi_slave *slave)
- __attribute__((weak, alias("__spi_cs_deactivate")));
__weak from linux/compiler.h
+int __spi_cs_is_valid(unsigned int bus, unsigned int cs) +{
- return 1;
+}
+void __spi_cs_activate(struct spi_slave *slave) +{
- /* do nothing */
+}
+void __spi_cs_deactivate(struct spi_slave *slave) +{
- /* do nothing */
+}
+void spi_init() +{
- /* do nothing */
+}
+/*
- ARM PL022 exists in different 'flavors'.
- This drivers currently support the standard variant (0x00041022), that has a
- 16bit wide and 8 locations deep TX/RX FIFO.
- */
+static int pl022_is_supported(struct pl022_spi_slave *ps) +{
- /* PL022 version is 0x00041022 */
- if ((readw(ps->regs + SSP_PID0) == 0x22) &&
(readw(ps->regs + SSP_PID1) == 0x10) &&((readw(ps->regs + SSP_PID2) & 0xf) == 0x04) &&(readw(ps->regs + SSP_PID3) == 0x00))return 1;- return 0;
+}
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int mode)+{
- struct pl022_spi_slave *ps;
- u16 scr = 1, prescaler, cr0 = 0, cpsr = 0;
- if (!spi_cs_is_valid(bus, cs))
return NULL;- ps = malloc(sizeof(*ps));
- if (!ps)
return NULL;- ps->slave.bus = bus;
- ps->slave.cs = cs;
- ps->freq = max_hz;
- switch (bus) {
- case 0:
ps->regs = (void *)CONFIG_SYS_SPI_BASE;break;+#ifdef CONFIG_SYS_SPI_BASE1
- case 1:
ps->regs = (void *)CONFIG_SYS_SPI_BASE1;break;+#endif +#ifdef CONFIG_SYS_SPI_BASE2
- case 2:
ps->regs = (void *)CONFIG_SYS_SPI_BASE2;break;+#endif +#ifdef CONFIG_SYS_SPI_BASE3
- case 3:
ps->regs = (void *)CONFIG_SYS_SPI_BASE3;break;+#endif
- default:
free(ps);return NULL;- }
- /* Check the PL022 version */
- if (!pl022_is_supported(ps)) {
free(ps);return NULL;- }
- /* Set requested polarity and 8bit mode */
- cr0 = SSP_CR0_8BIT_MODE;
- cr0 |= (mode & SPI_CPHA) ? SSP_CR0_SPH : 0;
- cr0 |= (mode & SPI_CPOL) ? SSP_CR0_SPO : 0;
- writew(cr0, ps->regs + SSP_CR0);
- /* Program the SSPClk frequency */
- prescaler = CONFIG_SYS_SPI_CLK / ps->freq;
- if (prescaler <= 0xFF)
cpsr = prescaler;- else {
for (scr = 1; scr <= SSP_SCR_MAX; scr++) {if (!(prescaler % scr)) {cpsr = prescaler / scr;if (cpsr <= SSP_CPSR_MAX)break;}}if (scr > SSP_SCR_MAX) {scr = SSP_SCR_MAX;cpsr = prescaler / scr;cpsr &= SSP_CPSR_MAX;}- }
- if (cpsr & 0x1)
cpsr++;- writew(cpsr, ps->regs + SSP_CPSR);
- cr0 = readw(ps->regs + SSP_CR0);
- writew(cr0 | (scr - 1) << SSP_SCR_SHFT, ps->regs + SSP_CR0);
- return &ps->slave;
+}
+void spi_free_slave(struct spi_slave *slave) +{
- struct pl022_spi_slave *ps = to_pl022_spi(slave);
- free(ps);
+}
+int spi_claim_bus(struct spi_slave *slave) +{
- struct pl022_spi_slave *ps = to_pl022_spi(slave);
- /* Enable the SPI hardware */
- writew(readw(ps->regs + SSP_CR1) | SSP_CR1_MASK_SSE,
ps->regs + SSP_CR1);- return 0;
+}
+void spi_release_bus(struct spi_slave *slave) +{
- struct pl022_spi_slave *ps = to_pl022_spi(slave);
- /* Disable the SPI hardware */
- writew(0x0, ps->regs + SSP_CR1);
+}
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)+{
- struct pl022_spi_slave *ps = to_pl022_spi(slave);
- u32 len_tx = 0, len_rx = 0, len;
- u32 ret = 0;
- const u8 *txp = dout;
- u8 *rxp = din, value;
- if (bitlen == 0)
/* Finish any previously submitted transfers */goto out;- /*
* TODO: The controller can do non-multiple-of-8 bit* transfers, but this driver currently doesn't support it.** It's also not clear how such transfers are supposed to be* represented as a stream of bytes...this is a limitation of* the current SPI interface.*/- if (bitlen % 8) {
ret = -1;/* Errors always terminate an ongoing transfer */flags |= SPI_XFER_END;goto out;- }
- len = bitlen / 8;
- if (flags & SPI_XFER_BEGIN)
spi_cs_activate(slave);- while (len_tx < len) {
if (readw(ps->regs + SSP_SR) & SSP_SR_MASK_TNF) {value = (txp != NULL) ? *txp++ : 0;writew(value, ps->regs + SSP_DR);len_tx++;}if (readw(ps->regs + SSP_SR) & SSP_SR_MASK_RNE) {value = readw(ps->regs + SSP_DR);if (rxp)*rxp++ = value;len_rx++;}- }
- while (len_rx < len_tx) {
if (readw(ps->regs + SSP_SR) & SSP_SR_MASK_RNE) {value = readw(ps->regs + SSP_DR);if (rxp)*rxp++ = value;len_rx++;}- }
+out:
- if (flags & SPI_XFER_END)
spi_cs_deactivate(slave);- return ret;
+}
Looks good.
Thanks, Stefan
On 12/12/2012 3:48 PM, Stefan Roese wrote:
On 12/06/2012 07:56 AM, Vipin Kumar wrote:
From: Armando Viscontiarmando.visconti@st.com
This patch adds the support for the ARM PL022 SPI controller for the standard variant (0x00041022), which has a 16bit wide and 8 locations deep TX/RX FIFO.
Signed-off-by: Armando Viscontiarmando.visconti@st.com Signed-off-by: Vipin Kumarvipin.kumar@st.com
Dear Wolfgang, Stefan,
There seems to be no direct owner of spi framework. So, I am directing this patch to you
A few comments below.
Regards Vipin
drivers/spi/Makefile | 1 + drivers/spi/pl022_spi.c | 308 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 309 insertions(+) create mode 100644 drivers/spi/pl022_spi.c
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 824d357..3a4e4b0 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -42,6 +42,7 @@ COBJS-$(CONFIG_MXC_SPI) += mxc_spi.o COBJS-$(CONFIG_MXS_SPI) += mxs_spi.o COBJS-$(CONFIG_OC_TINY_SPI) += oc_tiny_spi.o COBJS-$(CONFIG_OMAP3_SPI) += omap3_spi.o +COBJS-$(CONFIG_PL022_SPI) += pl022_spi.o COBJS-$(CONFIG_SOFT_SPI) += soft_spi.o COBJS-$(CONFIG_SH_SPI) += sh_spi.o COBJS-$(CONFIG_FSL_ESPI) += fsl_espi.o diff --git a/drivers/spi/pl022_spi.c b/drivers/spi/pl022_spi.c new file mode 100644 index 0000000..3ea769a --- /dev/null +++ b/drivers/spi/pl022_spi.c @@ -0,0 +1,308 @@ +/*
- (C) Copyright 2012
- Armando Visconti, ST Microelectronics, armando.visconti@st.com.
- Driver for ARM PL022 SPI Controller. Based on atmel_spi.c
- by Atmel Corporation.
- This program is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2 of
- the License, or (at your option) any later version.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- MA 02111-1307 USA
- */
+#include<common.h> +#include<malloc.h> +#include<spi.h> +#include<asm/io.h> +#include<asm/arch/hardware.h>
+/* SSP registers mapping */ +#define SSP_CR0 0x000 +#define SSP_CR1 0x004 +#define SSP_DR 0x008 +#define SSP_SR 0x00C +#define SSP_CPSR 0x010 +#define SSP_IMSC 0x014 +#define SSP_RIS 0x018 +#define SSP_MIS 0x01C +#define SSP_ICR 0x020 +#define SSP_DMACR 0x024 +#define SSP_ITCR 0x080 +#define SSP_ITIP 0x084 +#define SSP_ITOP 0x088 +#define SSP_TDR 0x08C
Please use C-structs instead to access the registers.
May be this patch is a ripped version from linux. That's why Thanks. I will do this in v2
+#define SSP_PID0 0xFE0 +#define SSP_PID1 0xFE4 +#define SSP_PID2 0xFE8 +#define SSP_PID3 0xFEC
+#define SSP_CID0 0xFF0 +#define SSP_CID1 0xFF4 +#define SSP_CID2 0xFF8 +#define SSP_CID3 0xFFC
+/* SSP Control Register 0 - SSP_CR0 */ +#define SSP_CR0_SPO (0x1<< 6) +#define SSP_CR0_SPH (0x1<< 7) +#define SSP_CR0_8BIT_MODE (0x07) +#define SSP_SCR_MAX (0xFF) +#define SSP_SCR_SHFT 8
+/* SSP Control Register 0 - SSP_CR1 */ +#define SSP_CR1_MASK_SSE (0x1<< 1)
+#define SSP_CPSR_MAX (0xFE)
+/* SSP Status Register - SSP_SR */ +#define SSP_SR_MASK_TFE (0x1<< 0) /* Transmit FIFO empty */ +#define SSP_SR_MASK_TNF (0x1<< 1) /* Transmit FIFO not full */ +#define SSP_SR_MASK_RNE (0x1<< 2) /* Receive FIFO not empty */ +#define SSP_SR_MASK_RFF (0x1<< 3) /* Receive FIFO full */ +#define SSP_SR_MASK_BSY (0x1<< 4) /* Busy Flag */
+struct pl022_spi_slave {
- struct spi_slave slave;
- void *regs;
- unsigned int freq;
+};
+static inline struct pl022_spi_slave *to_pl022_spi(struct spi_slave *slave) +{
- return container_of(slave, struct pl022_spi_slave, slave);
+}
+/*
- Following three functions should be provided by the
- board support package.
- */
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
- __attribute__((weak, alias("__spi_cs_is_valid")));
+void spi_cs_activate(struct spi_slave *slave)
- __attribute__((weak, alias("__spi_cs_activate")));
+void spi_cs_deactivate(struct spi_slave *slave)
- __attribute__((weak, alias("__spi_cs_deactivate")));
__weak from linux/compiler.h
OK
+int __spi_cs_is_valid(unsigned int bus, unsigned int cs) +{
- return 1;
+}
+void __spi_cs_activate(struct spi_slave *slave) +{
- /* do nothing */
+}
+void __spi_cs_deactivate(struct spi_slave *slave) +{
- /* do nothing */
+}
+void spi_init() +{
- /* do nothing */
+}
+/*
- ARM PL022 exists in different 'flavors'.
- This drivers currently support the standard variant (0x00041022), that has a
- 16bit wide and 8 locations deep TX/RX FIFO.
- */
+static int pl022_is_supported(struct pl022_spi_slave *ps) +{
- /* PL022 version is 0x00041022 */
- if ((readw(ps->regs + SSP_PID0) == 0x22)&&
(readw(ps->regs + SSP_PID1) == 0x10)&&((readw(ps->regs + SSP_PID2)& 0xf) == 0x04)&&(readw(ps->regs + SSP_PID3) == 0x00))return 1;- return 0;
+}
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int mode)+{
- struct pl022_spi_slave *ps;
- u16 scr = 1, prescaler, cr0 = 0, cpsr = 0;
- if (!spi_cs_is_valid(bus, cs))
return NULL;- ps = malloc(sizeof(*ps));
- if (!ps)
return NULL;- ps->slave.bus = bus;
- ps->slave.cs = cs;
- ps->freq = max_hz;
- switch (bus) {
- case 0:
ps->regs = (void *)CONFIG_SYS_SPI_BASE;break;+#ifdef CONFIG_SYS_SPI_BASE1
- case 1:
ps->regs = (void *)CONFIG_SYS_SPI_BASE1;break;+#endif +#ifdef CONFIG_SYS_SPI_BASE2
- case 2:
ps->regs = (void *)CONFIG_SYS_SPI_BASE2;break;+#endif +#ifdef CONFIG_SYS_SPI_BASE3
- case 3:
ps->regs = (void *)CONFIG_SYS_SPI_BASE3;break;+#endif
- default:
free(ps);return NULL;- }
- /* Check the PL022 version */
- if (!pl022_is_supported(ps)) {
free(ps);return NULL;- }
- /* Set requested polarity and 8bit mode */
- cr0 = SSP_CR0_8BIT_MODE;
- cr0 |= (mode& SPI_CPHA) ? SSP_CR0_SPH : 0;
- cr0 |= (mode& SPI_CPOL) ? SSP_CR0_SPO : 0;
- writew(cr0, ps->regs + SSP_CR0);
- /* Program the SSPClk frequency */
- prescaler = CONFIG_SYS_SPI_CLK / ps->freq;
- if (prescaler<= 0xFF)
cpsr = prescaler;- else {
for (scr = 1; scr<= SSP_SCR_MAX; scr++) {if (!(prescaler % scr)) {cpsr = prescaler / scr;if (cpsr<= SSP_CPSR_MAX)break;}}if (scr> SSP_SCR_MAX) {scr = SSP_SCR_MAX;cpsr = prescaler / scr;cpsr&= SSP_CPSR_MAX;}- }
- if (cpsr& 0x1)
cpsr++;- writew(cpsr, ps->regs + SSP_CPSR);
- cr0 = readw(ps->regs + SSP_CR0);
- writew(cr0 | (scr - 1)<< SSP_SCR_SHFT, ps->regs + SSP_CR0);
- return&ps->slave;
+}
+void spi_free_slave(struct spi_slave *slave) +{
- struct pl022_spi_slave *ps = to_pl022_spi(slave);
- free(ps);
+}
+int spi_claim_bus(struct spi_slave *slave) +{
- struct pl022_spi_slave *ps = to_pl022_spi(slave);
- /* Enable the SPI hardware */
- writew(readw(ps->regs + SSP_CR1) | SSP_CR1_MASK_SSE,
ps->regs + SSP_CR1);- return 0;
+}
+void spi_release_bus(struct spi_slave *slave) +{
- struct pl022_spi_slave *ps = to_pl022_spi(slave);
- /* Disable the SPI hardware */
- writew(0x0, ps->regs + SSP_CR1);
+}
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)+{
- struct pl022_spi_slave *ps = to_pl022_spi(slave);
- u32 len_tx = 0, len_rx = 0, len;
- u32 ret = 0;
- const u8 *txp = dout;
- u8 *rxp = din, value;
- if (bitlen == 0)
/* Finish any previously submitted transfers */goto out;- /*
* TODO: The controller can do non-multiple-of-8 bit* transfers, but this driver currently doesn't support it.** It's also not clear how such transfers are supposed to be* represented as a stream of bytes...this is a limitation of* the current SPI interface.*/- if (bitlen % 8) {
ret = -1;/* Errors always terminate an ongoing transfer */flags |= SPI_XFER_END;goto out;- }
- len = bitlen / 8;
- if (flags& SPI_XFER_BEGIN)
spi_cs_activate(slave);- while (len_tx< len) {
if (readw(ps->regs + SSP_SR)& SSP_SR_MASK_TNF) {value = (txp != NULL) ? *txp++ : 0;writew(value, ps->regs + SSP_DR);len_tx++;}if (readw(ps->regs + SSP_SR)& SSP_SR_MASK_RNE) {value = readw(ps->regs + SSP_DR);if (rxp)*rxp++ = value;len_rx++;}- }
- while (len_rx< len_tx) {
if (readw(ps->regs + SSP_SR)& SSP_SR_MASK_RNE) {value = readw(ps->regs + SSP_DR);if (rxp)*rxp++ = value;len_rx++;}- }
+out:
- if (flags& SPI_XFER_END)
spi_cs_deactivate(slave);- return ret;
+}
Looks good.
Thanks..will send v2 very soon
Thanks, Stefan
.
+/* SSP registers mapping */ +#define SSP_CR0 0x000 +#define SSP_CR1 0x004 +#define SSP_DR 0x008 +#define SSP_SR 0x00C +#define SSP_CPSR 0x010 +#define SSP_IMSC 0x014 +#define SSP_RIS 0x018 +#define SSP_MIS 0x01C +#define SSP_ICR 0x020 +#define SSP_DMACR 0x024 +#define SSP_ITCR 0x080 +#define SSP_ITIP 0x084 +#define SSP_ITOP 0x088 +#define SSP_TDR 0x08C
Please use C-structs instead to access the registers.
May be this patch is a ripped version from linux. That's why Thanks. I will do this in v2
Yes, I took this part from the linux pl022 driver.
Never understood which way (C-struct or defines) is preferable and why...
Rgds, Arm
On 12/12/2012 4:40 PM, Armando VISCONTI wrote:
+/* SSP registers mapping */ +#define SSP_CR0 0x000 +#define SSP_CR1 0x004 +#define SSP_DR 0x008 +#define SSP_SR 0x00C +#define SSP_CPSR 0x010 +#define SSP_IMSC 0x014 +#define SSP_RIS 0x018 +#define SSP_MIS 0x01C +#define SSP_ICR 0x020 +#define SSP_DMACR 0x024 +#define SSP_ITCR 0x080 +#define SSP_ITIP 0x084 +#define SSP_ITOP 0x088 +#define SSP_TDR 0x08C
Please use C-structs instead to access the registers.
May be this patch is a ripped version from linux. That's why Thanks. I will do this in v2
Yes, I took this part from the linux pl022 driver.
Never understood which way (C-struct or defines) is preferable and why...
U-boot uses the structure way(I do not exactly understand why) and the kernel code uses both ways I would change it to use the structure
Rgds, Arm
Vipin
On 12/12/2012 12:10 PM, Armando Visconti wrote:
+/* SSP registers mapping */ +#define SSP_CR0 0x000 +#define SSP_CR1 0x004 +#define SSP_DR 0x008 +#define SSP_SR 0x00C +#define SSP_CPSR 0x010 +#define SSP_IMSC 0x014 +#define SSP_RIS 0x018 +#define SSP_MIS 0x01C +#define SSP_ICR 0x020 +#define SSP_DMACR 0x024 +#define SSP_ITCR 0x080 +#define SSP_ITIP 0x084 +#define SSP_ITOP 0x088 +#define SSP_TDR 0x08C
Please use C-structs instead to access the registers.
May be this patch is a ripped version from linux. That's why Thanks. I will do this in v2
Yes, I took this part from the linux pl022 driver.
Never understood which way (C-struct or defines) is preferable and why...
U-Boot is here more strict than Linux here. Using C-struct's enables type-checking. So thats the preferred way.
Thanks, Stefan
participants (3)
-
Armando Visconti -
Stefan Roese -
Vipin Kumar