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-rw-r--r--drivers/spi/Makefile1
-rw-r--r--drivers/spi/atmel_spi.c210
-rw-r--r--drivers/spi/atmel_spi.h95
3 files changed, 306 insertions, 0 deletions
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index bc8a104121..e66e0ee092 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -26,6 +26,7 @@ include $(TOPDIR)/config.mk
LIB := $(obj)libspi.a
COBJS-y += mpc8xxx_spi.o
+COBJS-$(CONFIG_ATMEL_SPI) += atmel_spi.o
COBJS-$(CONFIG_MXC_SPI) += mxc_spi.o
COBJS := $(COBJS-y)
diff --git a/drivers/spi/atmel_spi.c b/drivers/spi/atmel_spi.c
new file mode 100644
index 0000000000..317c0b41b6
--- /dev/null
+++ b/drivers/spi/atmel_spi.c
@@ -0,0 +1,210 @@
+/*
+ * Copyright (C) 2007 Atmel Corporation
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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 <spi.h>
+#include <malloc.h>
+
+#include <asm/io.h>
+
+#include <asm/arch/clk.h>
+#include <asm/arch/memory-map.h>
+
+#include "atmel_spi.h"
+
+void spi_init()
+{
+
+}
+
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
+ unsigned int max_hz, unsigned int mode)
+{
+ struct atmel_spi_slave *as;
+ unsigned int scbr;
+ u32 csrx;
+ void *regs;
+
+ if (cs > 3 || !spi_cs_is_valid(bus, cs))
+ return NULL;
+
+ switch (bus) {
+ case 0:
+ regs = (void *)SPI0_BASE;
+ break;
+#ifdef SPI1_BASE
+ case 1:
+ regs = (void *)SPI1_BASE;
+ break;
+#endif
+#ifdef SPI2_BASE
+ case 2:
+ regs = (void *)SPI2_BASE;
+ break;
+#endif
+#ifdef SPI3_BASE
+ case 3:
+ regs = (void *)SPI3_BASE;
+ break;
+#endif
+ default:
+ return NULL;
+ }
+
+
+ scbr = (get_spi_clk_rate(bus) + max_hz - 1) / max_hz;
+ if (scbr > ATMEL_SPI_CSRx_SCBR_MAX)
+ /* Too low max SCK rate */
+ return NULL;
+ if (scbr < 1)
+ scbr = 1;
+
+ csrx = ATMEL_SPI_CSRx_SCBR(scbr);
+ csrx |= ATMEL_SPI_CSRx_BITS(ATMEL_SPI_BITS_8);
+ if (!(mode & SPI_CPHA))
+ csrx |= ATMEL_SPI_CSRx_NCPHA;
+ if (mode & SPI_CPOL)
+ csrx |= ATMEL_SPI_CSRx_CPOL;
+
+ as = malloc(sizeof(struct atmel_spi_slave));
+ if (!as)
+ return NULL;
+
+ as->slave.bus = bus;
+ as->slave.cs = cs;
+ as->regs = regs;
+ as->mr = ATMEL_SPI_MR_MSTR | ATMEL_SPI_MR_MODFDIS
+ | ATMEL_SPI_MR_PCS(~(1 << cs) & 0xf);
+ spi_writel(as, CSR(cs), csrx);
+
+ return &as->slave;
+}
+
+void spi_free_slave(struct spi_slave *slave)
+{
+ struct atmel_spi_slave *as = to_atmel_spi(slave);
+
+ free(as);
+}
+
+int spi_claim_bus(struct spi_slave *slave)
+{
+ struct atmel_spi_slave *as = to_atmel_spi(slave);
+
+ /* Enable the SPI hardware */
+ spi_writel(as, CR, ATMEL_SPI_CR_SPIEN);
+
+ /*
+ * Select the slave. This should set SCK to the correct
+ * initial state, etc.
+ */
+ spi_writel(as, MR, as->mr);
+
+ return 0;
+}
+
+void spi_release_bus(struct spi_slave *slave)
+{
+ struct atmel_spi_slave *as = to_atmel_spi(slave);
+
+ /* Disable the SPI hardware */
+ spi_writel(as, CR, ATMEL_SPI_CR_SPIDIS);
+}
+
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
+ const void *dout, void *din, unsigned long flags)
+{
+ struct atmel_spi_slave *as = to_atmel_spi(slave);
+ unsigned int len_tx;
+ unsigned int len_rx;
+ unsigned int len;
+ int ret;
+ u32 status;
+ const u8 *txp = dout;
+ u8 *rxp = din;
+ u8 value;
+
+ ret = 0;
+ 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) {
+ /* Errors always terminate an ongoing transfer */
+ flags |= SPI_XFER_END;
+ goto out;
+ }
+
+ len = bitlen / 8;
+
+ /*
+ * The controller can do automatic CS control, but it is
+ * somewhat quirky, and it doesn't really buy us much anyway
+ * in the context of U-Boot.
+ */
+ if (flags & SPI_XFER_BEGIN)
+ spi_cs_activate(slave);
+
+ for (len_tx = 0, len_rx = 0; len_rx < len; ) {
+ status = spi_readl(as, SR);
+
+ if (status & ATMEL_SPI_SR_OVRES)
+ return -1;
+
+ if (len_tx < len && (status & ATMEL_SPI_SR_TDRE)) {
+ if (txp)
+ value = *txp++;
+ else
+ value = 0;
+ spi_writel(as, TDR, value);
+ len_tx++;
+ }
+ if (status & ATMEL_SPI_SR_RDRF) {
+ value = spi_readl(as, RDR);
+ if (rxp)
+ *rxp++ = value;
+ len_rx++;
+ }
+ }
+
+out:
+ if (flags & SPI_XFER_END) {
+ /*
+ * Wait until the transfer is completely done before
+ * we deactivate CS.
+ */
+ do {
+ status = spi_readl(as, SR);
+ } while (!(status & ATMEL_SPI_SR_TXEMPTY));
+
+ spi_cs_deactivate(slave);
+ }
+
+ return 0;
+}
diff --git a/drivers/spi/atmel_spi.h b/drivers/spi/atmel_spi.h
new file mode 100644
index 0000000000..8b69a6d215
--- /dev/null
+++ b/drivers/spi/atmel_spi.h
@@ -0,0 +1,95 @@
+/*
+ * Register definitions for the Atmel AT32/AT91 SPI Controller
+ */
+
+/* Register offsets */
+#define ATMEL_SPI_CR 0x0000
+#define ATMEL_SPI_MR 0x0004
+#define ATMEL_SPI_RDR 0x0008
+#define ATMEL_SPI_TDR 0x000c
+#define ATMEL_SPI_SR 0x0010
+#define ATMEL_SPI_IER 0x0014
+#define ATMEL_SPI_IDR 0x0018
+#define ATMEL_SPI_IMR 0x001c
+#define ATMEL_SPI_CSR(x) (0x0030 + 4 * (x))
+#define ATMEL_SPI_VERSION 0x00fc
+
+/* Bits in CR */
+#define ATMEL_SPI_CR_SPIEN (1 << 0)
+#define ATMEL_SPI_CR_SPIDIS (1 << 1)
+#define ATMEL_SPI_CR_SWRST (1 << 7)
+#define ATMEL_SPI_CR_LASTXFER (1 << 24)
+
+/* Bits in MR */
+#define ATMEL_SPI_MR_MSTR (1 << 0)
+#define ATMEL_SPI_MR_PS (1 << 1)
+#define ATMEL_SPI_MR_PCSDEC (1 << 2)
+#define ATMEL_SPI_MR_FDIV (1 << 3)
+#define ATMEL_SPI_MR_MODFDIS (1 << 4)
+#define ATMEL_SPI_MR_LLB (1 << 7)
+#define ATMEL_SPI_MR_PCS(x) (((x) & 15) << 16)
+#define ATMEL_SPI_MR_DLYBCS(x) ((x) << 24)
+
+/* Bits in RDR */
+#define ATMEL_SPI_RDR_RD(x) (x)
+#define ATMEL_SPI_RDR_PCS(x) ((x) << 16)
+
+/* Bits in TDR */
+#define ATMEL_SPI_TDR_TD(x) (x)
+#define ATMEL_SPI_TDR_PCS(x) ((x) << 16)
+#define ATMEL_SPI_TDR_LASTXFER (1 << 24)
+
+/* Bits in SR/IER/IDR/IMR */
+#define ATMEL_SPI_SR_RDRF (1 << 0)
+#define ATMEL_SPI_SR_TDRE (1 << 1)
+#define ATMEL_SPI_SR_MODF (1 << 2)
+#define ATMEL_SPI_SR_OVRES (1 << 3)
+#define ATMEL_SPI_SR_ENDRX (1 << 4)
+#define ATMEL_SPI_SR_ENDTX (1 << 5)
+#define ATMEL_SPI_SR_RXBUFF (1 << 6)
+#define ATMEL_SPI_SR_TXBUFE (1 << 7)
+#define ATMEL_SPI_SR_NSSR (1 << 8)
+#define ATMEL_SPI_SR_TXEMPTY (1 << 9)
+#define ATMEL_SPI_SR_SPIENS (1 << 16)
+
+/* Bits in CSRx */
+#define ATMEL_SPI_CSRx_CPOL (1 << 0)
+#define ATMEL_SPI_CSRx_NCPHA (1 << 1)
+#define ATMEL_SPI_CSRx_CSAAT (1 << 3)
+#define ATMEL_SPI_CSRx_BITS(x) ((x) << 4)
+#define ATMEL_SPI_CSRx_SCBR(x) ((x) << 8)
+#define ATMEL_SPI_CSRx_SCBR_MAX 0xff
+#define ATMEL_SPI_CSRx_DLYBS(x) ((x) << 16)
+#define ATMEL_SPI_CSRx_DLYBCT(x) ((x) << 24)
+
+/* Bits in VERSION */
+#define ATMEL_SPI_VERSION_REV(x) ((x) << 0)
+#define ATMEL_SPI_VERSION_MFN(x) ((x) << 16)
+
+/* Constants for CSRx:BITS */
+#define ATMEL_SPI_BITS_8 0
+#define ATMEL_SPI_BITS_9 1
+#define ATMEL_SPI_BITS_10 2
+#define ATMEL_SPI_BITS_11 3
+#define ATMEL_SPI_BITS_12 4
+#define ATMEL_SPI_BITS_13 5
+#define ATMEL_SPI_BITS_14 6
+#define ATMEL_SPI_BITS_15 7
+#define ATMEL_SPI_BITS_16 8
+
+struct atmel_spi_slave {
+ struct spi_slave slave;
+ void *regs;
+ u32 mr;
+};
+
+static inline struct atmel_spi_slave *to_atmel_spi(struct spi_slave *slave)
+{
+ return container_of(slave, struct atmel_spi_slave, slave);
+}
+
+/* Register access macros */
+#define spi_readl(as, reg) \
+ readl(as->regs + ATMEL_SPI_##reg)
+#define spi_writel(as, reg, value) \
+ writel(value, as->regs + ATMEL_SPI_##reg)
generated by cgit (git 2.34.1) at 2024-12-24 19:48:19 +0000