*/
#include <common.h>
+#include <clk.h>
#include <dm.h>
#include <errno.h>
#include <malloc.h>
SPI_MODE_EN = BIT(31 - 7), /* Enable interface */
SPI_MODE_LEN_MASK = 0xf00000,
+ SPI_MODE_LEN_SHIFT = 20,
+ SPI_MODE_PM_SHIFT = 16,
SPI_MODE_PM_MASK = 0xf0000,
SPI_COM_LST = BIT(31 - 9),
struct mpc8xxx_priv {
spi8xxx_t *spi;
struct gpio_desc gpios[16];
- int max_cs;
+ int cs_count;
+ ulong clk_rate;
};
-static inline u32 to_prescale_mod(u32 val)
-{
- return (min(val, (u32)15) << 16);
-}
-
-static void set_char_len(spi8xxx_t *spi, u32 val)
-{
- clrsetbits_be32(&spi->mode, SPI_MODE_LEN_MASK, (val << 20));
-}
-
#define SPI_TIMEOUT 1000
-static int __spi_set_speed(spi8xxx_t *spi, uint speed)
-{
- /* TODO(mario.six@gdsys.cc): This only ever sets one fixed speed */
-
- /* Use SYSCLK / 8 (16.67MHz typ.) */
- clrsetbits_be32(&spi->mode, SPI_MODE_PM_MASK, to_prescale_mod(1));
-
- return 0;
-}
-
static int mpc8xxx_spi_ofdata_to_platdata(struct udevice *dev)
{
struct mpc8xxx_priv *priv = dev_get_priv(dev);
+ struct clk clk;
int ret;
priv->spi = (spi8xxx_t *)dev_read_addr(dev);
- /* TODO(mario.six@gdsys.cc): Read clock and save the value */
-
ret = gpio_request_list_by_name(dev, "gpios", priv->gpios,
ARRAY_SIZE(priv->gpios), GPIOD_IS_OUT | GPIOD_ACTIVE_LOW);
if (ret < 0)
return -EINVAL;
- priv->max_cs = ret;
+ priv->cs_count = ret;
+
+ ret = clk_get_by_index(dev, 0, &clk);
+ if (ret) {
+ dev_err(dev, "%s: clock not defined\n", __func__);
+ return ret;
+ }
+
+ priv->clk_rate = clk_get_rate(&clk);
+ if (!priv->clk_rate) {
+ dev_err(dev, "%s: failed to get clock rate\n", __func__);
+ return -EINVAL;
+ }
return 0;
}
static int mpc8xxx_spi_probe(struct udevice *dev)
{
struct mpc8xxx_priv *priv = dev_get_priv(dev);
+ spi8xxx_t *spi = priv->spi;
/*
* SPI pins on the MPC83xx are not muxed, so all we do is initialize
* some registers
*/
- out_be32(&priv->spi->mode, SPI_MODE_REV | SPI_MODE_MS | SPI_MODE_EN);
+ out_be32(&priv->spi->mode, SPI_MODE_REV | SPI_MODE_MS);
+
+ /* set len to 8 bits */
+ setbits_be32(&spi->mode, (8 - 1) << SPI_MODE_LEN_SHIFT);
- __spi_set_speed(priv->spi, 16666667);
+ setbits_be32(&spi->mode, SPI_MODE_EN);
/* Clear all SPI events */
setbits_be32(&priv->spi->event, 0xffffffff);
struct mpc8xxx_priv *priv = dev_get_priv(bus);
spi8xxx_t *spi = priv->spi;
struct dm_spi_slave_platdata *platdata = dev_get_parent_platdata(dev);
- u32 tmpdin = 0;
- int num_blks = DIV_ROUND_UP(bitlen, 32);
+ u32 tmpdin = 0, tmpdout = 0, n;
+ const u8 *cout = dout;
+ u8 *cin = din;
debug("%s: slave %s:%u dout %08X din %08X bitlen %u\n", __func__,
- bus->name, platdata->cs, *(uint *)dout, *(uint *)din, bitlen);
+ bus->name, platdata->cs, (uint)dout, (uint)din, bitlen);
+ if (platdata->cs >= priv->cs_count) {
+ dev_err(dev, "chip select index %d too large (cs_count=%d)\n",
+ platdata->cs, priv->cs_count);
+ return -EINVAL;
+ }
+ if (bitlen % 8) {
+ printf("*** spi_xfer: bitlen must be multiple of 8\n");
+ return -ENOTSUPP;
+ }
if (flags & SPI_XFER_BEGIN)
mpc8xxx_spi_cs_activate(dev);
/* Clear all SPI events */
setbits_be32(&spi->event, 0xffffffff);
+ n = bitlen / 8;
- /* Handle data in 32-bit chunks */
- while (num_blks--) {
- u32 tmpdout = 0;
- uchar xfer_bitlen = (bitlen >= 32 ? 32 : bitlen);
+ /* Handle data in 8-bit chunks */
+ while (n--) {
ulong start;
- clrbits_be32(&spi->mode, SPI_MODE_EN);
-
- /* Set up length for this transfer */
-
- if (bitlen <= 4) /* 4 bits or less */
- set_char_len(spi, 3);
- else if (bitlen <= 16) /* at most 16 bits */
- set_char_len(spi, bitlen - 1);
- else /* more than 16 bits -> full 32 bit transfer */
- set_char_len(spi, 0);
-
- setbits_be32(&spi->mode, SPI_MODE_EN);
-
- /* Shift data so it's msb-justified */
- tmpdout = *(u32 *)dout >> (32 - xfer_bitlen);
-
- if (bitlen > 32) {
- /* Set up the next iteration if sending > 32 bits */
- bitlen -= 32;
- dout += 4;
- }
+ if (cout)
+ tmpdout = *cout++;
/* Write the data out */
out_be32(&spi->tx, tmpdout);
tmpdin = in_be32(&spi->rx);
setbits_be32(&spi->event, SPI_EV_NE);
- *(u32 *)din = (tmpdin << (32 - xfer_bitlen));
- if (xfer_bitlen == 32) {
- /* Advance output buffer by 32 bits */
- din += 4;
- }
+ if (cin)
+ *cin++ = tmpdin;
/*
* Only bail when we've had both NE and NF events.
static int mpc8xxx_spi_set_speed(struct udevice *dev, uint speed)
{
struct mpc8xxx_priv *priv = dev_get_priv(dev);
+ spi8xxx_t *spi = priv->spi;
+ u32 bits, mask, div16, pm;
+ u32 mode;
+ ulong clk;
+
+ clk = priv->clk_rate;
+ if (clk / 64 > speed) {
+ div16 = SPI_MODE_DIV16;
+ clk /= 16;
+ } else {
+ div16 = 0;
+ }
+ pm = (clk - 1)/(4*speed) + 1;
+ if (pm > 16) {
+ dev_err(dev, "requested speed %u too small\n", speed);
+ return -EINVAL;
+ }
+ pm--;
+
+ bits = div16 | (pm << SPI_MODE_PM_SHIFT);
+ mask = SPI_MODE_DIV16 | SPI_MODE_PM_MASK;
+ mode = in_be32(&spi->mode);
+ if ((mode & mask) != bits) {
+ /* Must clear mode[EN] while changing speed. */
+ mode &= ~(mask | SPI_MODE_EN);
+ out_be32(&spi->mode, mode);
+ mode |= bits;
+ out_be32(&spi->mode, mode);
+ mode |= SPI_MODE_EN;
+ out_be32(&spi->mode, mode);
+ }
- return __spi_set_speed(priv->spi, speed);
+ debug("requested speed %u, set speed to %lu/(%s4*%u) == %lu\n",
+ speed, priv->clk_rate, div16 ? "16*" : "", pm + 1,
+ clk/(4*(pm + 1)));
+
+ return 0;
}
static int mpc8xxx_spi_set_mode(struct udevice *dev, uint mode)
projects / oweals / u-boot.git / blobdiff