1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (c) 2006 Ben Warren, Qstreams Networks Inc.
4 * With help from the common/soft_spi and arch/powerpc/cpu/mpc8260 drivers
13 #include <asm/mpc8xxx_spi.h>
14 #include <asm-generic/gpio.h>
15 #include <dm/device_compat.h>
18 SPI_EV_NE = BIT(31 - 22), /* Receiver Not Empty */
19 SPI_EV_NF = BIT(31 - 23), /* Transmitter Not Full */
23 SPI_MODE_LOOP = BIT(31 - 1), /* Loopback mode */
24 SPI_MODE_CI = BIT(31 - 2), /* Clock invert */
25 SPI_MODE_CP = BIT(31 - 3), /* Clock phase */
26 SPI_MODE_DIV16 = BIT(31 - 4), /* Divide clock source by 16 */
27 SPI_MODE_REV = BIT(31 - 5), /* Reverse mode - MSB first */
28 SPI_MODE_MS = BIT(31 - 6), /* Always master */
29 SPI_MODE_EN = BIT(31 - 7), /* Enable interface */
31 SPI_MODE_LEN_MASK = 0xf00000,
32 SPI_MODE_LEN_SHIFT = 20,
33 SPI_MODE_PM_SHIFT = 16,
34 SPI_MODE_PM_MASK = 0xf0000,
36 SPI_COM_LST = BIT(31 - 9),
41 struct gpio_desc gpios[16];
46 #define SPI_TIMEOUT 1000
48 static int mpc8xxx_spi_ofdata_to_platdata(struct udevice *dev)
50 struct mpc8xxx_priv *priv = dev_get_priv(dev);
54 priv->spi = (spi8xxx_t *)dev_read_addr(dev);
56 ret = gpio_request_list_by_name(dev, "gpios", priv->gpios,
57 ARRAY_SIZE(priv->gpios), GPIOD_IS_OUT | GPIOD_ACTIVE_LOW);
63 ret = clk_get_by_index(dev, 0, &clk);
65 dev_err(dev, "%s: clock not defined\n", __func__);
69 priv->clk_rate = clk_get_rate(&clk);
70 if (!priv->clk_rate) {
71 dev_err(dev, "%s: failed to get clock rate\n", __func__);
78 static int mpc8xxx_spi_probe(struct udevice *dev)
80 struct mpc8xxx_priv *priv = dev_get_priv(dev);
81 spi8xxx_t *spi = priv->spi;
84 * SPI pins on the MPC83xx are not muxed, so all we do is initialize
87 out_be32(&priv->spi->mode, SPI_MODE_REV | SPI_MODE_MS);
89 /* set len to 8 bits */
90 setbits_be32(&spi->mode, (8 - 1) << SPI_MODE_LEN_SHIFT);
92 setbits_be32(&spi->mode, SPI_MODE_EN);
94 /* Clear all SPI events */
95 setbits_be32(&priv->spi->event, 0xffffffff);
96 /* Mask all SPI interrupts */
97 clrbits_be32(&priv->spi->mask, 0xffffffff);
98 /* LST bit doesn't do anything, so disregard */
99 out_be32(&priv->spi->com, 0);
104 static void mpc8xxx_spi_cs_activate(struct udevice *dev)
106 struct mpc8xxx_priv *priv = dev_get_priv(dev->parent);
107 struct dm_spi_slave_platdata *platdata = dev_get_parent_platdata(dev);
109 dm_gpio_set_dir_flags(&priv->gpios[platdata->cs], GPIOD_IS_OUT);
110 dm_gpio_set_value(&priv->gpios[platdata->cs], 0);
113 static void mpc8xxx_spi_cs_deactivate(struct udevice *dev)
115 struct mpc8xxx_priv *priv = dev_get_priv(dev->parent);
116 struct dm_spi_slave_platdata *platdata = dev_get_parent_platdata(dev);
118 dm_gpio_set_dir_flags(&priv->gpios[platdata->cs], GPIOD_IS_OUT);
119 dm_gpio_set_value(&priv->gpios[platdata->cs], 1);
122 static int mpc8xxx_spi_xfer(struct udevice *dev, uint bitlen,
123 const void *dout, void *din, ulong flags)
125 struct udevice *bus = dev->parent;
126 struct mpc8xxx_priv *priv = dev_get_priv(bus);
127 spi8xxx_t *spi = priv->spi;
128 struct dm_spi_slave_platdata *platdata = dev_get_parent_platdata(dev);
129 u32 tmpdin = 0, tmpdout = 0, n;
130 const u8 *cout = dout;
133 debug("%s: slave %s:%u dout %08X din %08X bitlen %u\n", __func__,
134 bus->name, platdata->cs, (uint)dout, (uint)din, bitlen);
135 if (platdata->cs >= priv->cs_count) {
136 dev_err(dev, "chip select index %d too large (cs_count=%d)\n",
137 platdata->cs, priv->cs_count);
141 printf("*** spi_xfer: bitlen must be multiple of 8\n");
145 if (flags & SPI_XFER_BEGIN)
146 mpc8xxx_spi_cs_activate(dev);
148 /* Clear all SPI events */
149 setbits_be32(&spi->event, 0xffffffff);
152 /* Handle data in 8-bit chunks */
159 /* Write the data out */
160 out_be32(&spi->tx, tmpdout);
162 debug("*** %s: ... %08x written\n", __func__, tmpdout);
165 * Wait for SPI transmit to get out
166 * or time out (1 second = 1000 ms)
167 * The NE event must be read and cleared first
169 start = get_timer(0);
171 u32 event = in_be32(&spi->event);
172 bool have_ne = event & SPI_EV_NE;
173 bool have_nf = event & SPI_EV_NF;
178 tmpdin = in_be32(&spi->rx);
179 setbits_be32(&spi->event, SPI_EV_NE);
185 * Only bail when we've had both NE and NF events.
186 * This will cause timeouts on RO devices, so maybe
187 * in the future put an arbitrary delay after writing
188 * the device. Arbitrary delays suck, though...
194 } while (get_timer(start) < SPI_TIMEOUT);
196 if (get_timer(start) >= SPI_TIMEOUT) {
197 debug("*** %s: Time out during SPI transfer\n",
202 debug("*** %s: transfer ended. Value=%08x\n", __func__, tmpdin);
205 if (flags & SPI_XFER_END)
206 mpc8xxx_spi_cs_deactivate(dev);
211 static int mpc8xxx_spi_set_speed(struct udevice *dev, uint speed)
213 struct mpc8xxx_priv *priv = dev_get_priv(dev);
214 spi8xxx_t *spi = priv->spi;
215 u32 bits, mask, div16, pm;
219 clk = priv->clk_rate;
220 if (clk / 64 > speed) {
221 div16 = SPI_MODE_DIV16;
226 pm = (clk - 1)/(4*speed) + 1;
228 dev_err(dev, "requested speed %u too small\n", speed);
233 bits = div16 | (pm << SPI_MODE_PM_SHIFT);
234 mask = SPI_MODE_DIV16 | SPI_MODE_PM_MASK;
235 mode = in_be32(&spi->mode);
236 if ((mode & mask) != bits) {
237 /* Must clear mode[EN] while changing speed. */
238 mode &= ~(mask | SPI_MODE_EN);
239 out_be32(&spi->mode, mode);
241 out_be32(&spi->mode, mode);
243 out_be32(&spi->mode, mode);
246 debug("requested speed %u, set speed to %lu/(%s4*%u) == %lu\n",
247 speed, priv->clk_rate, div16 ? "16*" : "", pm + 1,
253 static int mpc8xxx_spi_set_mode(struct udevice *dev, uint mode)
255 /* TODO(mario.six@gdsys.cc): Using SPI_CPHA (for clock phase) and
256 * SPI_CPOL (for clock polarity) should work
261 static const struct dm_spi_ops mpc8xxx_spi_ops = {
262 .xfer = mpc8xxx_spi_xfer,
263 .set_speed = mpc8xxx_spi_set_speed,
264 .set_mode = mpc8xxx_spi_set_mode,
266 * cs_info is not needed, since we require all chip selects to be
267 * in the device tree explicitly
271 static const struct udevice_id mpc8xxx_spi_ids[] = {
272 { .compatible = "fsl,spi" },
276 U_BOOT_DRIVER(mpc8xxx_spi) = {
277 .name = "mpc8xxx_spi",
279 .of_match = mpc8xxx_spi_ids,
280 .ops = &mpc8xxx_spi_ops,
281 .ofdata_to_platdata = mpc8xxx_spi_ofdata_to_platdata,
282 .probe = mpc8xxx_spi_probe,
283 .priv_auto_alloc_size = sizeof(struct mpc8xxx_priv),