--- /dev/null
+/*
+ * Copyright (c) 2010-2013 NVIDIA Corporation
+ * With help from the mpc8xxx SPI driver
+ * With more help from omap3_spi SPI driver
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <asm/io.h>
+#include <asm/gpio.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/pinmux.h>
+#include <asm/arch-tegra/clk_rst.h>
+#include <asm/arch-tegra20/tegra20_sflash.h>
+#include <spi.h>
+#include <fdtdec.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define SPI_CMD_GO (1 << 30)
+#define SPI_CMD_ACTIVE_SCLK_SHIFT 26
+#define SPI_CMD_ACTIVE_SCLK_MASK (3 << SPI_CMD_ACTIVE_SCLK_SHIFT)
+#define SPI_CMD_CK_SDA (1 << 21)
+#define SPI_CMD_ACTIVE_SDA_SHIFT 18
+#define SPI_CMD_ACTIVE_SDA_MASK (3 << SPI_CMD_ACTIVE_SDA_SHIFT)
+#define SPI_CMD_CS_POL (1 << 16)
+#define SPI_CMD_TXEN (1 << 15)
+#define SPI_CMD_RXEN (1 << 14)
+#define SPI_CMD_CS_VAL (1 << 13)
+#define SPI_CMD_CS_SOFT (1 << 12)
+#define SPI_CMD_CS_DELAY (1 << 9)
+#define SPI_CMD_CS3_EN (1 << 8)
+#define SPI_CMD_CS2_EN (1 << 7)
+#define SPI_CMD_CS1_EN (1 << 6)
+#define SPI_CMD_CS0_EN (1 << 5)
+#define SPI_CMD_BIT_LENGTH (1 << 4)
+#define SPI_CMD_BIT_LENGTH_MASK 0x0000001F
+
+#define SPI_STAT_BSY (1 << 31)
+#define SPI_STAT_RDY (1 << 30)
+#define SPI_STAT_RXF_FLUSH (1 << 29)
+#define SPI_STAT_TXF_FLUSH (1 << 28)
+#define SPI_STAT_RXF_UNR (1 << 27)
+#define SPI_STAT_TXF_OVF (1 << 26)
+#define SPI_STAT_RXF_EMPTY (1 << 25)
+#define SPI_STAT_RXF_FULL (1 << 24)
+#define SPI_STAT_TXF_EMPTY (1 << 23)
+#define SPI_STAT_TXF_FULL (1 << 22)
+#define SPI_STAT_SEL_TXRX_N (1 << 16)
+#define SPI_STAT_CUR_BLKCNT (1 << 15)
+
+#define SPI_TIMEOUT 1000
+#define TEGRA_SPI_MAX_FREQ 52000000
+
+struct spi_regs {
+ u32 command; /* SPI_COMMAND_0 register */
+ u32 status; /* SPI_STATUS_0 register */
+ u32 rx_cmp; /* SPI_RX_CMP_0 register */
+ u32 dma_ctl; /* SPI_DMA_CTL_0 register */
+ u32 tx_fifo; /* SPI_TX_FIFO_0 register */
+ u32 rsvd[3]; /* offsets 0x14 to 0x1F reserved */
+ u32 rx_fifo; /* SPI_RX_FIFO_0 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;
+};
+
+/* tegra20 only supports one SFLASH controller */
+static struct tegra_spi_ctrl spi_ctrls[1];
+
+static inline struct tegra_spi_slave *to_tegra_spi(struct spi_slave *slave)
+{
+ return container_of(slave, struct tegra_spi_slave, slave);
+}
+
+int tegra20_spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+ /* Tegra20 SPI-Flash - only 1 device ('bus/cs') */
+ if (bus != 0 || cs != 0)
+ return 0;
+ else
+ return 1;
+}
+
+struct spi_slave *tegra20_spi_setup_slave(unsigned int bus, unsigned int cs,
+ unsigned int max_hz, unsigned int mode)
+{
+ struct tegra_spi_slave *spi;
+
+ 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 = spi_alloc_slave(struct tegra_spi_slave, bus, cs);
+ if (!spi) {
+ printf("SPI error: malloc of SPI structure failed\n");
+ return NULL;
+ }
+ 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 tegra20_spi_free_slave(struct spi_slave *slave)
+{
+ struct tegra_spi_slave *spi = to_tegra_spi(slave);
+
+ free(spi);
+}
+
+int tegra20_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 slink register found\n", __func__);
+ continue;
+ }
+ ctrl->freq = fdtdec_get_int(gd->fdt_blob, node,
+ "spi-max-frequency", 0);
+ if (!ctrl->freq) {
+ debug("%s: no slink 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 tegra20_spi_claim_bus(struct spi_slave *slave)
+{
+ struct tegra_spi_slave *spi = to_tegra_spi(slave);
+ struct spi_regs *regs = spi->ctrl->regs;
+ u32 reg;
+
+ /* 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 */
+ reg = SPI_STAT_RDY | SPI_STAT_RXF_FLUSH | SPI_STAT_TXF_FLUSH | \
+ SPI_STAT_RXF_UNR | SPI_STAT_TXF_OVF;
+ writel(reg, ®s->status);
+ debug("%s: STATUS = %08x\n", __func__, readl(®s->status));
+
+ /*
+ * Use sw-controlled CS, so we can clock in data after ReadID, etc.
+ */
+ reg = (spi->ctrl->mode & 1) << SPI_CMD_ACTIVE_SDA_SHIFT;
+ if (spi->ctrl->mode & 2)
+ reg |= 1 << SPI_CMD_ACTIVE_SCLK_SHIFT;
+ clrsetbits_le32(®s->command, SPI_CMD_ACTIVE_SCLK_MASK |
+ SPI_CMD_ACTIVE_SDA_MASK, SPI_CMD_CS_SOFT | reg);
+ debug("%s: COMMAND = %08x\n", __func__, readl(®s->command));
+
+ /*
+ * SPI pins on Tegra20 are muxed - change pinmux later due to UART
+ * issue.
+ */
+ pinmux_set_func(PMUX_PINGRP_GMD, PMUX_FUNC_SFLASH);
+ pinmux_tristate_disable(PMUX_PINGRP_LSPI);
+ pinmux_set_func(PMUX_PINGRP_GMC, PMUX_FUNC_SFLASH);
+
+ return 0;
+}
+
+void tegra20_spi_cs_activate(struct spi_slave *slave)
+{
+ struct tegra_spi_slave *spi = to_tegra_spi(slave);
+ struct spi_regs *regs = spi->ctrl->regs;
+
+ /* CS is negated on Tegra, so drive a 1 to get a 0 */
+ setbits_le32(®s->command, SPI_CMD_CS_VAL);
+}
+
+void tegra20_spi_cs_deactivate(struct spi_slave *slave)
+{
+ struct tegra_spi_slave *spi = to_tegra_spi(slave);
+ struct spi_regs *regs = spi->ctrl->regs;
+
+ /* CS is negated on Tegra, so drive a 0 to get a 1 */
+ clrbits_le32(®s->command, SPI_CMD_CS_VAL);
+}
+
+int tegra20_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("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
+ slave->bus, slave->cs, *(u8 *)dout, *(u8 *)din, bitlen);
+ if (bitlen % 8)
+ return -1;
+ num_bytes = bitlen / 8;
+
+ ret = 0;
+
+ reg = readl(®s->status);
+ writel(reg, ®s->status); /* Clear all SPI events via R/W */
+ debug("spi_xfer entry: STATUS = %08x\n", reg);
+
+ reg = readl(®s->command);
+ reg |= SPI_CMD_TXEN | SPI_CMD_RXEN;
+ writel(reg, ®s->command);
+ debug("spi_xfer: COMMAND = %08x\n", readl(®s->command));
+
+ 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];
+ }
+
+ num_bytes -= bytes;
+ if (dout)
+ dout += bytes;
+
+ clrsetbits_le32(®s->command, SPI_CMD_BIT_LENGTH_MASK,
+ bytes * 8 - 1);
+ writel(tmpdout, ®s->tx_fifo);
+ setbits_le32(®s->command, SPI_CMD_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 status;
+
+ status = readl(®s->status);
+
+ /* We can exit when we've had both RX and TX activity */
+ if (is_read && (status & SPI_STAT_TXF_EMPTY))
+ break;
+
+ if ((status & (SPI_STAT_BSY | SPI_STAT_RDY)) !=
+ SPI_STAT_RDY)
+ tm++;
+
+ else if (!(status & SPI_STAT_RXF_EMPTY)) {
+ tmpdin = readl(®s->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(®s->status), ®s->status);
+ }
+
+ if (flags & SPI_XFER_END)
+ spi_cs_deactivate(slave);
+
+ debug("spi_xfer: transfer ended. Value=%08x, status = %08x\n",
+ tmpdin, readl(®s->status));
+
+ if (ret) {
+ printf("spi_xfer: timeout during SPI transfer, tm %d\n", ret);
+ return -1;
+ }
+
+ return 0;
+}
Code Review / kvmfornfv.git / blobdiff