tegra114: add SPI driver

Add driver for tegra114 SPI controller.  This controller is not
compatible with either the tegra20 or tegra30 controllers, so it
requires a new driver.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>

3 files changed, 421 insertions, 0 deletions

diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 3762d59..46e8fa3 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -49,6 +49,7 @@ COBJS-$(CONFIG_FSL_ESPI) += fsl_espi.o
 COBJS-$(CONFIG_FDT_SPI) += fdt_spi.o
 COBJS-$(CONFIG_TEGRA20_SFLASH) += tegra20_sflash.o
 COBJS-$(CONFIG_TEGRA20_SLINK) += tegra20_slink.o
+COBJS-$(CONFIG_TEGRA114_SPI) += tegra114_spi.o
 COBJS-$(CONFIG_XILINX_SPI) += xilinx_spi.o
 
 COBJS	:= $(COBJS-y)
diff --git a/drivers/spi/fdt_spi.c b/drivers/spi/fdt_spi.c
index c6ae719..58f139a 100644
--- a/drivers/spi/fdt_spi.c
+++ b/drivers/spi/fdt_spi.c
@@ -29,6 +29,7 @@
 #include <asm/arch-tegra/clk_rst.h>
 #include <asm/arch-tegra20/tegra20_sflash.h>
 #include <asm/arch-tegra20/tegra20_slink.h>
+#include <asm/arch-tegra114/tegra114_spi.h>
 #include <spi.h>
 #include <fdtdec.h>
 
@@ -79,6 +80,20 @@ static struct fdt_spi_driver fdt_spi_drivers[] = {
 		.xfer		= tegra30_spi_xfer,
 	},
 #endif
+#ifdef CONFIG_TEGRA114_SPI
+	{
+		.compat		= COMPAT_NVIDIA_TEGRA114_SPI,
+		.max_ctrls	= CONFIG_TEGRA114_SPI_CTRLS,
+		.init		= tegra114_spi_init,
+		.claim_bus	= tegra114_spi_claim_bus,
+		.cs_is_valid	= tegra114_spi_cs_is_valid,
+		.setup_slave	= tegra114_spi_setup_slave,
+		.free_slave	= tegra114_spi_free_slave,
+		.cs_activate	= tegra114_spi_cs_activate,
+		.cs_deactivate	= tegra114_spi_cs_deactivate,
+		.xfer		= tegra114_spi_xfer,
+	},
+#endif
 };
 
 static struct fdt_spi_driver *driver;
diff --git a/drivers/spi/tegra114_spi.c b/drivers/spi/tegra114_spi.c
new file mode 100644
index 0000000..b11a0a1
--- /dev/null
+++ b/drivers/spi/tegra114_spi.c
@@ -0,0 +1,405 @@
+/*
+ * NVIDIA Tegra SPI controller (T114 and later)
+ *
+ * Copyright (c) 2010-2013 NVIDIA Corporation
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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 <asm/io.h>
+#include <asm/gpio.h>
+#include <asm/arch/clock.h>
+#include <asm/arch-tegra/clk_rst.h>
+#include <asm/arch-tegra114/tegra114_spi.h>
+#include <spi.h>
+#include <fdtdec.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* COMMAND1 */
+#define SPI_CMD1_GO			(1 << 31)
+#define SPI_CMD1_M_S			(1 << 30)
+#define SPI_CMD1_MODE_MASK		0x3
+#define SPI_CMD1_MODE_SHIFT		28
+#define SPI_CMD1_CS_SEL_MASK		0x3
+#define SPI_CMD1_CS_SEL_SHIFT		26
+#define SPI_CMD1_CS_POL_INACTIVE3	(1 << 25)
+#define SPI_CMD1_CS_POL_INACTIVE2	(1 << 24)
+#define SPI_CMD1_CS_POL_INACTIVE1	(1 << 23)
+#define SPI_CMD1_CS_POL_INACTIVE0	(1 << 22)
+#define SPI_CMD1_CS_SW_HW		(1 << 21)
+#define SPI_CMD1_CS_SW_VAL		(1 << 20)
+#define SPI_CMD1_IDLE_SDA_MASK		0x3
+#define SPI_CMD1_IDLE_SDA_SHIFT		18
+#define SPI_CMD1_BIDIR			(1 << 17)
+#define SPI_CMD1_LSBI_FE		(1 << 16)
+#define SPI_CMD1_LSBY_FE		(1 << 15)
+#define SPI_CMD1_BOTH_EN_BIT		(1 << 14)
+#define SPI_CMD1_BOTH_EN_BYTE		(1 << 13)
+#define SPI_CMD1_RX_EN			(1 << 12)
+#define SPI_CMD1_TX_EN			(1 << 11)
+#define SPI_CMD1_PACKED			(1 << 5)
+#define SPI_CMD1_BIT_LEN_MASK		0x1F
+#define SPI_CMD1_BIT_LEN_SHIFT		0
+
+/* COMMAND2 */
+#define SPI_CMD2_TX_CLK_TAP_DELAY	(1 << 6)
+#define SPI_CMD2_TX_CLK_TAP_DELAY_MASK	(0x3F << 6)
+#define SPI_CMD2_RX_CLK_TAP_DELAY	(1 << 0)
+#define SPI_CMD2_RX_CLK_TAP_DELAY_MASK	(0x3F << 0)
+
+/* TRANSFER STATUS */
+#define SPI_XFER_STS_RDY		(1 << 30)
+
+/* FIFO STATUS */
+#define SPI_FIFO_STS_CS_INACTIVE	(1 << 31)
+#define SPI_FIFO_STS_FRAME_END		(1 << 30)
+#define SPI_FIFO_STS_RX_FIFO_FLUSH	(1 << 15)
+#define SPI_FIFO_STS_TX_FIFO_FLUSH	(1 << 14)
+#define SPI_FIFO_STS_ERR		(1 << 8)
+#define SPI_FIFO_STS_TX_FIFO_OVF	(1 << 7)
+#define SPI_FIFO_STS_TX_FIFO_UNR	(1 << 6)
+#define SPI_FIFO_STS_RX_FIFO_OVF	(1 << 5)
+#define SPI_FIFO_STS_RX_FIFO_UNR	(1 << 4)
+#define SPI_FIFO_STS_TX_FIFO_FULL	(1 << 3)
+#define SPI_FIFO_STS_TX_FIFO_EMPTY	(1 << 2)
+#define SPI_FIFO_STS_RX_FIFO_FULL	(1 << 1)
+#define SPI_FIFO_STS_RX_FIFO_EMPTY	(1 << 0)
+
+#define SPI_TIMEOUT		1000
+#define TEGRA_SPI_MAX_FREQ	52000000
+
+struct spi_regs {
+	u32 command1;	/* 000:SPI_COMMAND1 register */
+	u32 command2;	/* 004:SPI_COMMAND2 register */
+	u32 timing1;	/* 008:SPI_CS_TIM1 register */
+	u32 timing2;	/* 00c:SPI_CS_TIM2 register */
+	u32 xfer_status;/* 010:SPI_TRANS_STATUS register */
+	u32 fifo_status;/* 014:SPI_FIFO_STATUS register */
+	u32 tx_data;	/* 018:SPI_TX_DATA register */
+	u32 rx_data;	/* 01c:SPI_RX_DATA register */
+	u32 dma_ctl;	/* 020:SPI_DMA_CTL register */
+	u32 dma_blk;	/* 024:SPI_DMA_BLK register */
+	u32 rsvd[56];	/* 028-107 reserved */
+	u32 tx_fifo;	/* 108:SPI_FIFO1 register */
+	u32 rsvd2[31];	/* 10c-187 reserved */
+	u32 rx_fifo;	/* 188:SPI_FIFO2 register */
+	u32 spare_ctl;	/* 18c:SPI_SPARE_CTRL register */
+};
+
+struct tegra_spi_ctrl {
+	struct spi_regs *regs;
+	unsigned int freq;
+	unsigned int mode;
+	int periph_id;
+	int valid;
+};
+
+struct tegra_spi_slave {
+	struct spi_slave slave;
+	struct tegra_spi_ctrl *ctrl;
+};
+
+static struct tegra_spi_ctrl spi_ctrls[CONFIG_TEGRA114_SPI_CTRLS];
+
+static inline struct tegra_spi_slave *to_tegra_spi(struct spi_slave *slave)
+{
+	return container_of(slave, struct tegra_spi_slave, slave);
+}
+
+int tegra114_spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+	if (bus >= CONFIG_TEGRA114_SPI_CTRLS || cs > 3 || !spi_ctrls[bus].valid)
+		return 0;
+	else
+		return 1;
+}
+
+struct spi_slave *tegra114_spi_setup_slave(unsigned int bus, unsigned int cs,
+		unsigned int max_hz, unsigned int mode)
+{
+	struct tegra_spi_slave *spi;
+
+	debug("%s: bus: %u, cs: %u, max_hz: %u, mode: %u\n", __func__,
+		bus, cs, max_hz, mode);
+
+	if (!spi_cs_is_valid(bus, cs)) {
+		printf("SPI error: unsupported bus %d / chip select %d\n",
+		       bus, cs);
+		return NULL;
+	}
+
+	if (max_hz > TEGRA_SPI_MAX_FREQ) {
+		printf("SPI error: unsupported frequency %d Hz. Max frequency"
+			" is %d Hz\n", max_hz, TEGRA_SPI_MAX_FREQ);
+		return NULL;
+	}
+
+	spi = malloc(sizeof(struct tegra_spi_slave));
+	if (!spi) {
+		printf("SPI error: malloc of SPI structure failed\n");
+		return NULL;
+	}
+	spi->slave.bus = bus;
+	spi->slave.cs = cs;
+	spi->ctrl = &spi_ctrls[bus];
+	if (!spi->ctrl) {
+		printf("SPI error: could not find controller for bus %d\n",
+		       bus);
+		return NULL;
+	}
+
+	if (max_hz < spi->ctrl->freq) {
+		debug("%s: limiting frequency from %u to %u\n", __func__,
+		      spi->ctrl->freq, max_hz);
+		spi->ctrl->freq = max_hz;
+	}
+	spi->ctrl->mode = mode;
+
+	return &spi->slave;
+}
+
+void tegra114_spi_free_slave(struct spi_slave *slave)
+{
+	struct tegra_spi_slave *spi = to_tegra_spi(slave);
+
+	free(spi);
+}
+
+int tegra114_spi_init(int *node_list, int count)
+{
+	struct tegra_spi_ctrl *ctrl;
+	int i;
+	int node = 0;
+	int found = 0;
+
+	for (i = 0; i < count; i++) {
+		ctrl = &spi_ctrls[i];
+		node = node_list[i];
+
+		ctrl->regs = (struct spi_regs *)fdtdec_get_addr(gd->fdt_blob,
+								 node, "reg");
+		if ((fdt_addr_t)ctrl->regs == FDT_ADDR_T_NONE) {
+			debug("%s: no spi register found\n", __func__);
+			continue;
+		}
+		ctrl->freq = fdtdec_get_int(gd->fdt_blob, node,
+					    "spi-max-frequency", 0);
+		if (!ctrl->freq) {
+			debug("%s: no spi max frequency found\n", __func__);
+			continue;
+		}
+
+		ctrl->periph_id = clock_decode_periph_id(gd->fdt_blob, node);
+		if (ctrl->periph_id == PERIPH_ID_NONE) {
+			debug("%s: could not decode periph id\n", __func__);
+			continue;
+		}
+		ctrl->valid = 1;
+		found = 1;
+
+		debug("%s: found controller at %p, freq = %u, periph_id = %d\n",
+		      __func__, ctrl->regs, ctrl->freq, ctrl->periph_id);
+	}
+
+	return !found;
+}
+
+int tegra114_spi_claim_bus(struct spi_slave *slave)
+{
+	struct tegra_spi_slave *spi = to_tegra_spi(slave);
+	struct spi_regs *regs = spi->ctrl->regs;
+
+	/* Change SPI clock to correct frequency, PLLP_OUT0 source */
+	clock_start_periph_pll(spi->ctrl->periph_id, CLOCK_ID_PERIPH,
+			       spi->ctrl->freq);
+
+	/* Clear stale status here */
+	setbits_le32(&regs->fifo_status,
+		     SPI_FIFO_STS_ERR		|
+		     SPI_FIFO_STS_TX_FIFO_OVF	|
+		     SPI_FIFO_STS_TX_FIFO_UNR	|
+		     SPI_FIFO_STS_RX_FIFO_OVF	|
+		     SPI_FIFO_STS_RX_FIFO_UNR	|
+		     SPI_FIFO_STS_TX_FIFO_FULL	|
+		     SPI_FIFO_STS_TX_FIFO_EMPTY	|
+		     SPI_FIFO_STS_RX_FIFO_FULL	|
+		     SPI_FIFO_STS_RX_FIFO_EMPTY);
+	debug("%s: FIFO STATUS = %08x\n", __func__, readl(&regs->fifo_status));
+
+	/* Set master mode and sw controlled CS */
+	setbits_le32(&regs->command1, SPI_CMD1_M_S | SPI_CMD1_CS_SW_HW |
+		     (spi->ctrl->mode << SPI_CMD1_MODE_SHIFT));
+	debug("%s: COMMAND1 = %08x\n", __func__, readl(&regs->command1));
+
+	return 0;
+}
+
+void tegra114_spi_cs_activate(struct spi_slave *slave)
+{
+	struct tegra_spi_slave *spi = to_tegra_spi(slave);
+	struct spi_regs *regs = spi->ctrl->regs;
+
+	clrbits_le32(&regs->command1, SPI_CMD1_CS_SW_VAL);
+}
+
+void tegra114_spi_cs_deactivate(struct spi_slave *slave)
+{
+	struct tegra_spi_slave *spi = to_tegra_spi(slave);
+	struct spi_regs *regs = spi->ctrl->regs;
+
+	setbits_le32(&regs->command1, SPI_CMD1_CS_SW_VAL);
+}
+
+int tegra114_spi_xfer(struct spi_slave *slave, unsigned int bitlen,
+		const void *data_out, void *data_in, unsigned long flags)
+{
+	struct tegra_spi_slave *spi = to_tegra_spi(slave);
+	struct spi_regs *regs = spi->ctrl->regs;
+	u32 reg, tmpdout, tmpdin = 0;
+	const u8 *dout = data_out;
+	u8 *din = data_in;
+	int num_bytes;
+	int ret;
+
+	debug("%s: slave %u:%u dout %p din %p bitlen %u\n",
+	      __func__, slave->bus, slave->cs, dout, din, bitlen);
+	if (bitlen % 8)
+		return -1;
+	num_bytes = bitlen / 8;
+
+	ret = 0;
+
+	/* clear all error status bits */
+	reg = readl(&regs->fifo_status);
+	writel(reg, &regs->fifo_status);
+
+	/* clear ready bit */
+	setbits_le32(&regs->xfer_status, SPI_XFER_STS_RDY);
+
+	clrsetbits_le32(&regs->command1, SPI_CMD1_CS_SW_VAL,
+			SPI_CMD1_RX_EN | SPI_CMD1_TX_EN | SPI_CMD1_LSBY_FE |
+			(slave->cs << SPI_CMD1_CS_SEL_SHIFT));
+
+	/* set xfer size to 1 block (32 bits) */
+	writel(0, &regs->dma_blk);
+
+	if (flags & SPI_XFER_BEGIN)
+		spi_cs_activate(slave);
+
+	/* handle data in 32-bit chunks */
+	while (num_bytes > 0) {
+		int bytes;
+		int is_read = 0;
+		int tm, i;
+
+		tmpdout = 0;
+		bytes = (num_bytes > 4) ?  4 : num_bytes;
+
+		if (dout != NULL) {
+			for (i = 0; i < bytes; ++i)
+				tmpdout = (tmpdout << 8) | dout[i];
+			dout += bytes;
+		}
+
+		num_bytes -= bytes;
+
+		clrsetbits_le32(&regs->command1,
+				SPI_CMD1_BIT_LEN_MASK << SPI_CMD1_BIT_LEN_SHIFT,
+				(bytes * 8 - 1) << SPI_CMD1_BIT_LEN_SHIFT);
+		writel(tmpdout, &regs->tx_fifo);
+		setbits_le32(&regs->command1, SPI_CMD1_GO);
+
+		/*
+		 * Wait for SPI transmit FIFO to empty, or to time out.
+		 * The RX FIFO status will be read and cleared last
+		 */
+		for (tm = 0, is_read = 0; tm < SPI_TIMEOUT; ++tm) {
+			u32 fifo_status, xfer_status;
+
+			fifo_status = readl(&regs->fifo_status);
+
+			/* We can exit when we've had both RX and TX activity */
+			if (is_read &&
+			    (fifo_status & SPI_FIFO_STS_TX_FIFO_EMPTY))
+				break;
+
+			xfer_status = readl(&regs->xfer_status);
+			if (!(xfer_status & SPI_XFER_STS_RDY))
+				continue;
+
+			if (fifo_status & SPI_FIFO_STS_ERR) {
+				debug("%s: got a fifo error: ", __func__);
+				if (fifo_status & SPI_FIFO_STS_TX_FIFO_OVF)
+					debug("tx FIFO overflow ");
+				if (fifo_status & SPI_FIFO_STS_TX_FIFO_UNR)
+					debug("tx FIFO underrun ");
+				if (fifo_status & SPI_FIFO_STS_RX_FIFO_OVF)
+					debug("rx FIFO overflow ");
+				if (fifo_status & SPI_FIFO_STS_RX_FIFO_UNR)
+					debug("rx FIFO underrun ");
+				if (fifo_status & SPI_FIFO_STS_TX_FIFO_FULL)
+					debug("tx FIFO full ");
+				if (fifo_status & SPI_FIFO_STS_TX_FIFO_EMPTY)
+					debug("tx FIFO empty ");
+				if (fifo_status & SPI_FIFO_STS_RX_FIFO_FULL)
+					debug("rx FIFO full ");
+				if (fifo_status & SPI_FIFO_STS_RX_FIFO_EMPTY)
+					debug("rx FIFO empty ");
+				debug("\n");
+				break;
+			}
+
+			if (!(fifo_status & SPI_FIFO_STS_RX_FIFO_EMPTY)) {
+				tmpdin = readl(&regs->rx_fifo);
+				is_read = 1;
+
+				/* swap bytes read in */
+				if (din != NULL) {
+					for (i = bytes - 1; i >= 0; --i) {
+						din[i] = tmpdin & 0xff;
+						tmpdin >>= 8;
+					}
+					din += bytes;
+				}
+			}
+		}
+
+		if (tm >= SPI_TIMEOUT)
+			ret = tm;
+
+		/* clear ACK RDY, etc. bits */
+		writel(readl(&regs->fifo_status), &regs->fifo_status);
+	}
+
+	if (flags & SPI_XFER_END)
+		spi_cs_deactivate(slave);
+
+	debug("%s: transfer ended. Value=%08x, fifo_status = %08x\n",
+	      __func__, tmpdin, readl(&regs->fifo_status));
+
+	if (ret) {
+		printf("%s: timeout during SPI transfer, tm %d\n",
+		       __func__, ret);
+		return -1;
+	}
+
+	return 0;
+}