1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (c) 2010-2013 NVIDIA Corporation
4 * With help from the mpc8xxx SPI driver
5 * With more help from omap3_spi SPI driver
15 #include <asm/arch/clock.h>
16 #include <asm/arch/pinmux.h>
17 #include <asm/arch-tegra/clk_rst.h>
20 #include <linux/delay.h>
21 #include "tegra_spi.h"
23 DECLARE_GLOBAL_DATA_PTR;
25 #define SPI_CMD_GO BIT(30)
26 #define SPI_CMD_ACTIVE_SCLK_SHIFT 26
27 #define SPI_CMD_ACTIVE_SCLK_MASK (3 << SPI_CMD_ACTIVE_SCLK_SHIFT)
28 #define SPI_CMD_CK_SDA BIT(21)
29 #define SPI_CMD_ACTIVE_SDA_SHIFT 18
30 #define SPI_CMD_ACTIVE_SDA_MASK (3 << SPI_CMD_ACTIVE_SDA_SHIFT)
31 #define SPI_CMD_CS_POL BIT(16)
32 #define SPI_CMD_TXEN BIT(15)
33 #define SPI_CMD_RXEN BIT(14)
34 #define SPI_CMD_CS_VAL BIT(13)
35 #define SPI_CMD_CS_SOFT BIT(12)
36 #define SPI_CMD_CS_DELAY BIT(9)
37 #define SPI_CMD_CS3_EN BIT(8)
38 #define SPI_CMD_CS2_EN BIT(7)
39 #define SPI_CMD_CS1_EN BIT(6)
40 #define SPI_CMD_CS0_EN BIT(5)
41 #define SPI_CMD_BIT_LENGTH BIT(4)
42 #define SPI_CMD_BIT_LENGTH_MASK GENMASK(4, 0)
44 #define SPI_STAT_BSY BIT(31)
45 #define SPI_STAT_RDY BIT(30)
46 #define SPI_STAT_RXF_FLUSH BIT(29)
47 #define SPI_STAT_TXF_FLUSH BIT(28)
48 #define SPI_STAT_RXF_UNR BIT(27)
49 #define SPI_STAT_TXF_OVF BIT(26)
50 #define SPI_STAT_RXF_EMPTY BIT(25)
51 #define SPI_STAT_RXF_FULL BIT(24)
52 #define SPI_STAT_TXF_EMPTY BIT(23)
53 #define SPI_STAT_TXF_FULL BIT(22)
54 #define SPI_STAT_SEL_TXRX_N BIT(16)
55 #define SPI_STAT_CUR_BLKCNT BIT(15)
57 #define SPI_TIMEOUT 1000
58 #define TEGRA_SPI_MAX_FREQ 52000000
61 u32 command; /* SPI_COMMAND_0 register */
62 u32 status; /* SPI_STATUS_0 register */
63 u32 rx_cmp; /* SPI_RX_CMP_0 register */
64 u32 dma_ctl; /* SPI_DMA_CTL_0 register */
65 u32 tx_fifo; /* SPI_TX_FIFO_0 register */
66 u32 rsvd[3]; /* offsets 0x14 to 0x1F reserved */
67 u32 rx_fifo; /* SPI_RX_FIFO_0 register */
70 struct tegra20_sflash_priv {
71 struct spi_regs *regs;
76 int last_transaction_us;
79 int tegra20_sflash_cs_info(struct udevice *bus, unsigned int cs,
80 struct spi_cs_info *info)
82 /* Tegra20 SPI-Flash - only 1 device ('bus/cs') */
89 static int tegra20_sflash_ofdata_to_platdata(struct udevice *bus)
91 struct tegra_spi_platdata *plat = bus->platdata;
92 const void *blob = gd->fdt_blob;
93 int node = dev_of_offset(bus);
95 plat->base = devfdt_get_addr(bus);
96 plat->periph_id = clock_decode_periph_id(bus);
98 if (plat->periph_id == PERIPH_ID_NONE) {
99 debug("%s: could not decode periph id %d\n", __func__,
101 return -FDT_ERR_NOTFOUND;
104 /* Use 500KHz as a suitable default */
105 plat->frequency = fdtdec_get_int(blob, node, "spi-max-frequency",
107 plat->deactivate_delay_us = fdtdec_get_int(blob, node,
108 "spi-deactivate-delay", 0);
109 debug("%s: base=%#08lx, periph_id=%d, max-frequency=%d, deactivate_delay=%d\n",
110 __func__, plat->base, plat->periph_id, plat->frequency,
111 plat->deactivate_delay_us);
116 static int tegra20_sflash_probe(struct udevice *bus)
118 struct tegra_spi_platdata *plat = dev_get_platdata(bus);
119 struct tegra20_sflash_priv *priv = dev_get_priv(bus);
121 priv->regs = (struct spi_regs *)plat->base;
123 priv->last_transaction_us = timer_get_us();
124 priv->freq = plat->frequency;
125 priv->periph_id = plat->periph_id;
127 /* Change SPI clock to correct frequency, PLLP_OUT0 source */
128 clock_start_periph_pll(priv->periph_id, CLOCK_ID_PERIPH,
134 static int tegra20_sflash_claim_bus(struct udevice *dev)
136 struct udevice *bus = dev->parent;
137 struct tegra20_sflash_priv *priv = dev_get_priv(bus);
138 struct spi_regs *regs = priv->regs;
141 /* Change SPI clock to correct frequency, PLLP_OUT0 source */
142 clock_start_periph_pll(priv->periph_id, CLOCK_ID_PERIPH,
145 /* Clear stale status here */
146 reg = SPI_STAT_RDY | SPI_STAT_RXF_FLUSH | SPI_STAT_TXF_FLUSH | \
147 SPI_STAT_RXF_UNR | SPI_STAT_TXF_OVF;
148 writel(reg, ®s->status);
149 debug("%s: STATUS = %08x\n", __func__, readl(®s->status));
152 * Use sw-controlled CS, so we can clock in data after ReadID, etc.
154 reg = (priv->mode & 1) << SPI_CMD_ACTIVE_SDA_SHIFT;
156 reg |= 1 << SPI_CMD_ACTIVE_SCLK_SHIFT;
157 clrsetbits_le32(®s->command, SPI_CMD_ACTIVE_SCLK_MASK |
158 SPI_CMD_ACTIVE_SDA_MASK, SPI_CMD_CS_SOFT | reg);
159 debug("%s: COMMAND = %08x\n", __func__, readl(®s->command));
162 * SPI pins on Tegra20 are muxed - change pinmux later due to UART
165 pinmux_set_func(PMUX_PINGRP_GMD, PMUX_FUNC_SFLASH);
166 pinmux_tristate_disable(PMUX_PINGRP_LSPI);
167 pinmux_set_func(PMUX_PINGRP_GMC, PMUX_FUNC_SFLASH);
172 static void spi_cs_activate(struct udevice *dev)
174 struct udevice *bus = dev->parent;
175 struct tegra_spi_platdata *pdata = dev_get_platdata(bus);
176 struct tegra20_sflash_priv *priv = dev_get_priv(bus);
178 /* If it's too soon to do another transaction, wait */
179 if (pdata->deactivate_delay_us &&
180 priv->last_transaction_us) {
181 ulong delay_us; /* The delay completed so far */
182 delay_us = timer_get_us() - priv->last_transaction_us;
183 if (delay_us < pdata->deactivate_delay_us)
184 udelay(pdata->deactivate_delay_us - delay_us);
187 /* CS is negated on Tegra, so drive a 1 to get a 0 */
188 setbits_le32(&priv->regs->command, SPI_CMD_CS_VAL);
191 static void spi_cs_deactivate(struct udevice *dev)
193 struct udevice *bus = dev->parent;
194 struct tegra_spi_platdata *pdata = dev_get_platdata(bus);
195 struct tegra20_sflash_priv *priv = dev_get_priv(bus);
197 /* CS is negated on Tegra, so drive a 0 to get a 1 */
198 clrbits_le32(&priv->regs->command, SPI_CMD_CS_VAL);
200 /* Remember time of this transaction so we can honour the bus delay */
201 if (pdata->deactivate_delay_us)
202 priv->last_transaction_us = timer_get_us();
205 static int tegra20_sflash_xfer(struct udevice *dev, unsigned int bitlen,
206 const void *data_out, void *data_in,
209 struct udevice *bus = dev->parent;
210 struct tegra20_sflash_priv *priv = dev_get_priv(bus);
211 struct spi_regs *regs = priv->regs;
212 u32 reg, tmpdout, tmpdin = 0;
213 const u8 *dout = data_out;
218 debug("%s: slave %u:%u dout %p din %p bitlen %u\n",
219 __func__, bus->seq, spi_chip_select(dev), dout, din, bitlen);
222 num_bytes = bitlen / 8;
226 reg = readl(®s->status);
227 writel(reg, ®s->status); /* Clear all SPI events via R/W */
228 debug("spi_xfer entry: STATUS = %08x\n", reg);
230 reg = readl(®s->command);
231 reg |= SPI_CMD_TXEN | SPI_CMD_RXEN;
232 writel(reg, ®s->command);
233 debug("spi_xfer: COMMAND = %08x\n", readl(®s->command));
235 if (flags & SPI_XFER_BEGIN)
236 spi_cs_activate(dev);
238 /* handle data in 32-bit chunks */
239 while (num_bytes > 0) {
245 bytes = (num_bytes > 4) ? 4 : num_bytes;
248 for (i = 0; i < bytes; ++i)
249 tmpdout = (tmpdout << 8) | dout[i];
256 clrsetbits_le32(®s->command, SPI_CMD_BIT_LENGTH_MASK,
258 writel(tmpdout, ®s->tx_fifo);
259 setbits_le32(®s->command, SPI_CMD_GO);
262 * Wait for SPI transmit FIFO to empty, or to time out.
263 * The RX FIFO status will be read and cleared last
265 for (tm = 0, is_read = 0; tm < SPI_TIMEOUT; ++tm) {
268 status = readl(®s->status);
270 /* We can exit when we've had both RX and TX activity */
271 if (is_read && (status & SPI_STAT_TXF_EMPTY))
274 if ((status & (SPI_STAT_BSY | SPI_STAT_RDY)) !=
278 else if (!(status & SPI_STAT_RXF_EMPTY)) {
279 tmpdin = readl(®s->rx_fifo);
282 /* swap bytes read in */
284 for (i = bytes - 1; i >= 0; --i) {
285 din[i] = tmpdin & 0xff;
293 if (tm >= SPI_TIMEOUT)
296 /* clear ACK RDY, etc. bits */
297 writel(readl(®s->status), ®s->status);
300 if (flags & SPI_XFER_END)
301 spi_cs_deactivate(dev);
303 debug("spi_xfer: transfer ended. Value=%08x, status = %08x\n",
304 tmpdin, readl(®s->status));
307 printf("spi_xfer: timeout during SPI transfer, tm %d\n", ret);
314 static int tegra20_sflash_set_speed(struct udevice *bus, uint speed)
316 struct tegra_spi_platdata *plat = bus->platdata;
317 struct tegra20_sflash_priv *priv = dev_get_priv(bus);
319 if (speed > plat->frequency)
320 speed = plat->frequency;
322 debug("%s: regs=%p, speed=%d\n", __func__, priv->regs, priv->freq);
327 static int tegra20_sflash_set_mode(struct udevice *bus, uint mode)
329 struct tegra20_sflash_priv *priv = dev_get_priv(bus);
332 debug("%s: regs=%p, mode=%d\n", __func__, priv->regs, priv->mode);
337 static const struct dm_spi_ops tegra20_sflash_ops = {
338 .claim_bus = tegra20_sflash_claim_bus,
339 .xfer = tegra20_sflash_xfer,
340 .set_speed = tegra20_sflash_set_speed,
341 .set_mode = tegra20_sflash_set_mode,
342 .cs_info = tegra20_sflash_cs_info,
345 static const struct udevice_id tegra20_sflash_ids[] = {
346 { .compatible = "nvidia,tegra20-sflash" },
350 U_BOOT_DRIVER(tegra20_sflash) = {
351 .name = "tegra20_sflash",
353 .of_match = tegra20_sflash_ids,
354 .ops = &tegra20_sflash_ops,
355 .ofdata_to_platdata = tegra20_sflash_ofdata_to_platdata,
356 .platdata_auto_alloc_size = sizeof(struct tegra_spi_platdata),
357 .priv_auto_alloc_size = sizeof(struct tegra20_sflash_priv),
358 .probe = tegra20_sflash_probe,