Ciao Vipin,

On 12/12/2012 01:04 PM, Vipin KUMAR wrote:
From: Armando Visconti<armando.visco...@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.


Have you tested this patch on the new variant as well?
You should have a couple of boards there with the
new asic.

Signed-off-by: Armando Visconti<armando.visco...@st.com>
Signed-off-by: Vipin Kumar<vipin.ku...@st.com>
---
  drivers/spi/Makefile    |   1 +
  drivers/spi/pl022_spi.c | 310 ++++++++++++++++++++++++++++++++++++++++++++++++
  2 files changed, 311 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..ba018b8
--- /dev/null
+++ b/drivers/spi/pl022_spi.c
@@ -0,0 +1,310 @@
+/*
+ * (C) Copyright 2012
+ * Armando Visconti, ST Microelectronics, armando.visco...@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 */
+struct pl022 {
+       u32     ssp_cr0;        /* 0x000 */
+       u32     ssp_cr1;        /* 0x004 */
+       u32     ssp_dr;         /* 0x008 */
+       u32     ssp_sr;         /* 0x00c */
+       u32     ssp_cpsr;       /* 0x010 */
+       u32     ssp_imsc;       /* 0x014 */
+       u32     ssp_ris;        /* 0x018 */
+       u32     ssp_mis;        /* 0x01c */
+       u32     ssp_icr;        /* 0x020 */
+       u32     ssp_dmacr;      /* 0x024 */
+       u8      reserved_1[0x080 - 0x028];
+       u32     ssp_itcr;       /* 0x080 */
+       u32     ssp_itip;       /* 0x084 */
+       u32     ssp_itop;       /* 0x088 */
+       u32     ssp_tdr;        /* 0x08c */
+       u8      reserved_2[0xFE0 - 0x090];
+       u32     ssp_pid0;       /* 0xfe0 */
+       u32     ssp_pid1;       /* 0xfe4 */
+       u32     ssp_pid2;       /* 0xfe8 */
+       u32     ssp_pid3;       /* 0xfec */
+       u32     ssp_cid0;       /* 0xff0 */
+       u32     ssp_cid1;       /* 0xff4 */
+       u32     ssp_cid2;       /* 0xff8 */
+       u32     ssp_cid3;       /* 0xffc */
+};

It's correct!
:)

+
+/* 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 __weak spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+       return 1;
+}
+
+void __weak spi_cs_activate(struct spi_slave *slave)
+{
+       /* do nothing */
+}
+
+void __weak spi_cs_deactivate(struct spi_slave *slave)
+{
+       /* do nothing */
+}
+
+void spi_init()

Maybe you can put 'void' also in the arguments.
I think we forgot it in the original patch.

+{
+       /* 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)
+{
+       struct pl022 *pl022 = (struct pl022 *)ps->regs;
+
+       /* PL022 version is 0x00041022 */
+       if ((readw(pl022->ssp_pid0) == 0x22)&&
+               (readw(pl022->ssp_pid1) == 0x10)&&
+               ((readw(pl022->ssp_pid2)&  0xf) == 0x04)&&
+               (readw(pl022->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;
+       struct pl022 *pl022;
+       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;
+       }
+
+       pl022 = (struct pl022 *)ps->regs;
+
+       /* 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, pl022->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, pl022->ssp_cpsr);
+       cr0 = readw(pl022->ssp_cr0);
+       writew(cr0 | (scr - 1)<<  SSP_SCR_SHFT, pl022->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);
+       struct pl022 *pl022 = (struct pl022 *)ps->regs;
+
+       /* Enable the SPI hardware */
+       setbits_le16(pl022->ssp_cr1, SSP_CR1_MASK_SSE);
+
+       return 0;
+}
+
+void spi_release_bus(struct spi_slave *slave)
+{
+       struct pl022_spi_slave *ps = to_pl022_spi(slave);
+       struct pl022 *pl022 = (struct pl022 *)ps->regs;
+
+       /* Disable the SPI hardware */
+       writew(0x0, pl022->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);
+       struct pl022 *pl022 = (struct pl022 *)ps->regs;
+       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(pl022->ssp_sr)&  SSP_SR_MASK_TNF) {
+                       value = (txp != NULL) ? *txp++ : 0;
+                       writew(value, pl022->ssp_dr);
+                       len_tx++;
+               }
+
+               if (readw(pl022->ssp_sr)&  SSP_SR_MASK_RNE) {
+                       value = readw(pl022->ssp_dr);
+                       if (rxp)
+                               *rxp++ = value;
+                       len_rx++;
+               }
+       }
+
+       while (len_rx<  len_tx) {
+               if (readw(pl022->ssp_sr)&  SSP_SR_MASK_RNE) {
+                       value = readw(pl022->ssp_dr);
+                       if (rxp)
+                               *rxp++ = value;
+                       len_rx++;
+               }
+       }
+
+out:
+       if (flags&  SPI_XFER_END)
+               spi_cs_deactivate(slave);
+
+       return ret;
+}

Rest is fine.
I don't know if I need to ack it, but...

Acked-by: Armando Visconti <armando.visco...@st.com>

Ciao,
Arm

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