1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (C) 2008, Guennadi Liakhovetski <lg@denx.de>
11 #include <dm/device_compat.h>
12 #include <linux/errno.h>
15 #include <asm/arch/imx-regs.h>
16 #include <asm/arch/clock.h>
17 #include <asm/mach-imx/spi.h>
19 DECLARE_GLOBAL_DATA_PTR;
22 /* i.MX27 has a completely wrong register layout and register definitions in the
23 * datasheet, the correct one is in the Freescale's Linux driver */
25 #error "i.MX27 CSPI not supported due to drastic differences in register definitions" \
26 "See linux mxc_spi driver from Freescale for details."
29 __weak int board_spi_cs_gpio(unsigned bus, unsigned cs)
34 #define OUT MXC_GPIO_DIRECTION_OUT
36 #define reg_read readl
37 #define reg_write(a, v) writel(v, a)
39 #if !defined(CONFIG_SYS_SPI_MXC_WAIT)
40 #define CONFIG_SYS_SPI_MXC_WAIT (CONFIG_SYS_HZ/100) /* 10 ms */
43 #define MAX_CS_COUNT 4
45 struct mxc_spi_slave {
46 struct spi_slave slave;
49 #if defined(MXC_ECSPI)
57 struct gpio_desc cs_gpios[MAX_CS_COUNT];
61 static inline struct mxc_spi_slave *to_mxc_spi_slave(struct spi_slave *slave)
63 return container_of(slave, struct mxc_spi_slave, slave);
66 static void mxc_spi_cs_activate(struct mxc_spi_slave *mxcs)
68 #if defined(CONFIG_DM_SPI)
69 struct udevice *dev = mxcs->dev;
70 struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
72 u32 cs = slave_plat->cs;
74 if (!dm_gpio_is_valid(&mxcs->cs_gpios[cs]))
77 dm_gpio_set_value(&mxcs->cs_gpios[cs], 1);
80 gpio_set_value(mxcs->gpio, mxcs->ss_pol);
84 static void mxc_spi_cs_deactivate(struct mxc_spi_slave *mxcs)
86 #if defined(CONFIG_DM_SPI)
87 struct udevice *dev = mxcs->dev;
88 struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
90 u32 cs = slave_plat->cs;
92 if (!dm_gpio_is_valid(&mxcs->cs_gpios[cs]))
95 dm_gpio_set_value(&mxcs->cs_gpios[cs], 0);
98 gpio_set_value(mxcs->gpio, !(mxcs->ss_pol));
102 u32 get_cspi_div(u32 div)
106 for (i = 0; i < 8; i++) {
114 static s32 spi_cfg_mxc(struct mxc_spi_slave *mxcs, unsigned int cs)
116 unsigned int ctrl_reg;
119 unsigned int max_hz = mxcs->max_hz;
120 unsigned int mode = mxcs->mode;
122 clk_src = mxc_get_clock(MXC_CSPI_CLK);
124 div = DIV_ROUND_UP(clk_src, max_hz);
125 div = get_cspi_div(div);
127 debug("clk %d Hz, div %d, real clk %d Hz\n",
128 max_hz, div, clk_src / (4 << div));
130 ctrl_reg = MXC_CSPICTRL_CHIPSELECT(cs) |
131 MXC_CSPICTRL_BITCOUNT(MXC_CSPICTRL_MAXBITS) |
132 MXC_CSPICTRL_DATARATE(div) |
140 ctrl_reg |= MXC_CSPICTRL_PHA;
142 ctrl_reg |= MXC_CSPICTRL_POL;
143 if (mode & SPI_CS_HIGH)
144 ctrl_reg |= MXC_CSPICTRL_SSPOL;
145 mxcs->ctrl_reg = ctrl_reg;
152 static s32 spi_cfg_mxc(struct mxc_spi_slave *mxcs, unsigned int cs)
154 u32 clk_src = mxc_get_clock(MXC_CSPI_CLK);
155 s32 reg_ctrl, reg_config;
156 u32 ss_pol = 0, sclkpol = 0, sclkpha = 0, sclkctl = 0;
157 u32 pre_div = 0, post_div = 0;
158 struct cspi_regs *regs = (struct cspi_regs *)mxcs->base;
159 unsigned int max_hz = mxcs->max_hz;
160 unsigned int mode = mxcs->mode;
163 * Reset SPI and set all CSs to master mode, if toggling
164 * between slave and master mode we might see a glitch
167 reg_ctrl = MXC_CSPICTRL_MODE_MASK;
168 reg_write(®s->ctrl, reg_ctrl);
169 reg_ctrl |= MXC_CSPICTRL_EN;
170 reg_write(®s->ctrl, reg_ctrl);
172 if (clk_src > max_hz) {
173 pre_div = (clk_src - 1) / max_hz;
174 /* fls(1) = 1, fls(0x80000000) = 32, fls(16) = 5 */
175 post_div = fls(pre_div);
178 if (post_div >= 16) {
179 printf("Error: no divider for the freq: %d\n",
183 pre_div >>= post_div;
189 debug("pre_div = %d, post_div=%d\n", pre_div, post_div);
190 reg_ctrl = (reg_ctrl & ~MXC_CSPICTRL_SELCHAN(3)) |
191 MXC_CSPICTRL_SELCHAN(cs);
192 reg_ctrl = (reg_ctrl & ~MXC_CSPICTRL_PREDIV(0x0F)) |
193 MXC_CSPICTRL_PREDIV(pre_div);
194 reg_ctrl = (reg_ctrl & ~MXC_CSPICTRL_POSTDIV(0x0F)) |
195 MXC_CSPICTRL_POSTDIV(post_div);
197 if (mode & SPI_CS_HIGH)
200 if (mode & SPI_CPOL) {
208 reg_config = reg_read(®s->cfg);
211 * Configuration register setup
212 * The MX51 supports different setup for each SS
214 reg_config = (reg_config & ~(1 << (cs + MXC_CSPICON_SSPOL))) |
215 (ss_pol << (cs + MXC_CSPICON_SSPOL));
216 reg_config = (reg_config & ~(1 << (cs + MXC_CSPICON_POL))) |
217 (sclkpol << (cs + MXC_CSPICON_POL));
218 reg_config = (reg_config & ~(1 << (cs + MXC_CSPICON_CTL))) |
219 (sclkctl << (cs + MXC_CSPICON_CTL));
220 reg_config = (reg_config & ~(1 << (cs + MXC_CSPICON_PHA))) |
221 (sclkpha << (cs + MXC_CSPICON_PHA));
223 debug("reg_ctrl = 0x%x\n", reg_ctrl);
224 reg_write(®s->ctrl, reg_ctrl);
225 debug("reg_config = 0x%x\n", reg_config);
226 reg_write(®s->cfg, reg_config);
228 /* save config register and control register */
229 mxcs->ctrl_reg = reg_ctrl;
230 mxcs->cfg_reg = reg_config;
232 /* clear interrupt reg */
233 reg_write(®s->intr, 0);
234 reg_write(®s->stat, MXC_CSPICTRL_TC | MXC_CSPICTRL_RXOVF);
240 int spi_xchg_single(struct mxc_spi_slave *mxcs, unsigned int bitlen,
241 const u8 *dout, u8 *din, unsigned long flags)
243 int nbytes = DIV_ROUND_UP(bitlen, 8);
245 struct cspi_regs *regs = (struct cspi_regs *)mxcs->base;
249 debug("%s: bitlen %d dout 0x%lx din 0x%lx\n",
250 __func__, bitlen, (ulong)dout, (ulong)din);
252 mxcs->ctrl_reg = (mxcs->ctrl_reg &
253 ~MXC_CSPICTRL_BITCOUNT(MXC_CSPICTRL_MAXBITS)) |
254 MXC_CSPICTRL_BITCOUNT(bitlen - 1);
256 reg_write(®s->ctrl, mxcs->ctrl_reg | MXC_CSPICTRL_EN);
258 reg_write(®s->cfg, mxcs->cfg_reg);
261 /* Clear interrupt register */
262 reg_write(®s->stat, MXC_CSPICTRL_TC | MXC_CSPICTRL_RXOVF);
265 * The SPI controller works only with words,
266 * check if less than a word is sent.
267 * Access to the FIFO is only 32 bit
271 cnt = (bitlen % 32) / 8;
273 for (i = 0; i < cnt; i++) {
274 data = (data << 8) | (*dout++ & 0xFF);
277 debug("Sending SPI 0x%x\n", data);
279 reg_write(®s->txdata, data);
288 /* Buffer is not 32-bit aligned */
289 if ((unsigned long)dout & 0x03) {
291 for (i = 0; i < 4; i++)
292 data = (data << 8) | (*dout++ & 0xFF);
295 data = cpu_to_be32(data);
299 debug("Sending SPI 0x%x\n", data);
300 reg_write(®s->txdata, data);
304 /* FIFO is written, now starts the transfer setting the XCH bit */
305 reg_write(®s->ctrl, mxcs->ctrl_reg |
306 MXC_CSPICTRL_EN | MXC_CSPICTRL_XCH);
309 status = reg_read(®s->stat);
310 /* Wait until the TC (Transfer completed) bit is set */
311 while ((status & MXC_CSPICTRL_TC) == 0) {
312 if (get_timer(ts) > CONFIG_SYS_SPI_MXC_WAIT) {
313 printf("spi_xchg_single: Timeout!\n");
316 status = reg_read(®s->stat);
319 /* Transfer completed, clear any pending request */
320 reg_write(®s->stat, MXC_CSPICTRL_TC | MXC_CSPICTRL_RXOVF);
322 nbytes = DIV_ROUND_UP(bitlen, 8);
327 data = reg_read(®s->rxdata);
328 cnt = (bitlen % 32) / 8;
329 data = cpu_to_be32(data) >> ((sizeof(data) - cnt) * 8);
330 debug("SPI Rx unaligned: 0x%x\n", data);
332 memcpy(din, &data, cnt);
340 tmp = reg_read(®s->rxdata);
341 data = cpu_to_be32(tmp);
342 debug("SPI Rx: 0x%x 0x%x\n", tmp, data);
343 cnt = min_t(u32, nbytes, sizeof(data));
345 memcpy(din, &data, cnt);
355 static int mxc_spi_xfer_internal(struct mxc_spi_slave *mxcs,
356 unsigned int bitlen, const void *dout,
357 void *din, unsigned long flags)
359 int n_bytes = DIV_ROUND_UP(bitlen, 8);
363 u8 *p_outbuf = (u8 *)dout;
364 u8 *p_inbuf = (u8 *)din;
369 if (flags & SPI_XFER_BEGIN)
370 mxc_spi_cs_activate(mxcs);
372 while (n_bytes > 0) {
373 if (n_bytes < MAX_SPI_BYTES)
376 blk_size = MAX_SPI_BYTES;
378 n_bits = blk_size * 8;
380 ret = spi_xchg_single(mxcs, n_bits, p_outbuf, p_inbuf, 0);
385 p_outbuf += blk_size;
391 if (flags & SPI_XFER_END) {
392 mxc_spi_cs_deactivate(mxcs);
398 static int mxc_spi_claim_bus_internal(struct mxc_spi_slave *mxcs, int cs)
400 struct cspi_regs *regs = (struct cspi_regs *)mxcs->base;
403 reg_write(®s->rxdata, 1);
405 ret = spi_cfg_mxc(mxcs, cs);
407 printf("mxc_spi: cannot setup SPI controller\n");
410 reg_write(®s->period, MXC_CSPIPERIOD_32KHZ);
411 reg_write(®s->intr, 0);
416 #ifndef CONFIG_DM_SPI
417 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
418 void *din, unsigned long flags)
420 struct mxc_spi_slave *mxcs = to_mxc_spi_slave(slave);
422 return mxc_spi_xfer_internal(mxcs, bitlen, dout, din, flags);
426 * Some SPI devices require active chip-select over multiple
427 * transactions, we achieve this using a GPIO. Still, the SPI
428 * controller has to be configured to use one of its own chipselects.
429 * To use this feature you have to implement board_spi_cs_gpio() to assign
430 * a gpio value for each cs (-1 if cs doesn't need to use gpio).
431 * You must use some unused on this SPI controller cs between 0 and 3.
433 static int setup_cs_gpio(struct mxc_spi_slave *mxcs,
434 unsigned int bus, unsigned int cs)
438 mxcs->gpio = board_spi_cs_gpio(bus, cs);
439 if (mxcs->gpio == -1)
442 gpio_request(mxcs->gpio, "spi-cs");
443 ret = gpio_direction_output(mxcs->gpio, !(mxcs->ss_pol));
445 printf("mxc_spi: cannot setup gpio %d\n", mxcs->gpio);
452 static unsigned long spi_bases[] = {
453 MXC_SPI_BASE_ADDRESSES
456 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
457 unsigned int max_hz, unsigned int mode)
459 struct mxc_spi_slave *mxcs;
462 if (bus >= ARRAY_SIZE(spi_bases))
466 printf("Error: desired clock is 0\n");
470 mxcs = spi_alloc_slave(struct mxc_spi_slave, bus, cs);
472 puts("mxc_spi: SPI Slave not allocated !\n");
476 mxcs->ss_pol = (mode & SPI_CS_HIGH) ? 1 : 0;
478 ret = setup_cs_gpio(mxcs, bus, cs);
484 mxcs->base = spi_bases[bus];
485 mxcs->max_hz = max_hz;
491 void spi_free_slave(struct spi_slave *slave)
493 struct mxc_spi_slave *mxcs = to_mxc_spi_slave(slave);
498 int spi_claim_bus(struct spi_slave *slave)
500 struct mxc_spi_slave *mxcs = to_mxc_spi_slave(slave);
502 return mxc_spi_claim_bus_internal(mxcs, slave->cs);
505 void spi_release_bus(struct spi_slave *slave)
507 /* TODO: Shut the controller down */
511 static int mxc_spi_probe(struct udevice *bus)
513 struct mxc_spi_slave *mxcs = dev_get_platdata(bus);
514 int node = dev_of_offset(bus);
515 const void *blob = gd->fdt_blob;
519 ret = gpio_request_list_by_name(bus, "cs-gpios", mxcs->cs_gpios,
520 ARRAY_SIZE(mxcs->cs_gpios), 0);
522 pr_err("Can't get %s gpios! Error: %d", bus->name, ret);
526 for (i = 0; i < ARRAY_SIZE(mxcs->cs_gpios); i++) {
527 if (!dm_gpio_is_valid(&mxcs->cs_gpios[i]))
530 ret = dm_gpio_set_dir_flags(&mxcs->cs_gpios[i],
531 GPIOD_IS_OUT | GPIOD_ACTIVE_LOW);
533 dev_err(bus, "Setting cs %d error\n", i);
538 mxcs->base = devfdt_get_addr(bus);
539 if (mxcs->base == FDT_ADDR_T_NONE)
542 mxcs->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency",
548 static int mxc_spi_xfer(struct udevice *dev, unsigned int bitlen,
549 const void *dout, void *din, unsigned long flags)
551 struct mxc_spi_slave *mxcs = dev_get_platdata(dev->parent);
554 return mxc_spi_xfer_internal(mxcs, bitlen, dout, din, flags);
557 static int mxc_spi_claim_bus(struct udevice *dev)
559 struct mxc_spi_slave *mxcs = dev_get_platdata(dev->parent);
560 struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
564 return mxc_spi_claim_bus_internal(mxcs, slave_plat->cs);
567 static int mxc_spi_release_bus(struct udevice *dev)
572 static int mxc_spi_set_speed(struct udevice *bus, uint speed)
578 static int mxc_spi_set_mode(struct udevice *bus, uint mode)
580 struct mxc_spi_slave *mxcs = dev_get_platdata(bus);
583 mxcs->ss_pol = (mode & SPI_CS_HIGH) ? 1 : 0;
588 static const struct dm_spi_ops mxc_spi_ops = {
589 .claim_bus = mxc_spi_claim_bus,
590 .release_bus = mxc_spi_release_bus,
591 .xfer = mxc_spi_xfer,
592 .set_speed = mxc_spi_set_speed,
593 .set_mode = mxc_spi_set_mode,
596 static const struct udevice_id mxc_spi_ids[] = {
597 { .compatible = "fsl,imx51-ecspi" },
601 U_BOOT_DRIVER(mxc_spi) = {
604 .of_match = mxc_spi_ids,
606 .platdata_auto_alloc_size = sizeof(struct mxc_spi_slave),
607 .probe = mxc_spi_probe,