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-rw-r--r--drivers/spi/mpc8xxx_spi.c80
1 files changed, 27 insertions, 53 deletions
diff --git a/drivers/spi/mpc8xxx_spi.c b/drivers/spi/mpc8xxx_spi.c
index ac4d0a9bae..8ef2451411 100644
--- a/drivers/spi/mpc8xxx_spi.c
+++ b/drivers/spi/mpc8xxx_spi.c
@@ -27,6 +27,7 @@ enum {
SPI_MODE_EN = BIT(31 - 7), /* Enable interface */
SPI_MODE_LEN_MASK = 0xf00000,
+ SPI_MODE_LEN_SHIFT = 20,
SPI_MODE_PM_MASK = 0xf0000,
SPI_COM_LST = BIT(31 - 9),
@@ -43,23 +44,8 @@ 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);
@@ -82,14 +68,22 @@ static int mpc8xxx_spi_ofdata_to_platdata(struct udevice *dev)
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);
+ /* 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));
+
+ setbits_be32(&spi->mode, SPI_MODE_EN);
/* Clear all SPI events */
setbits_be32(&priv->spi->event, 0xffffffff);
@@ -126,50 +120,35 @@ static int mpc8xxx_spi_xfer(struct udevice *dev, uint bitlen,
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);
@@ -193,11 +172,8 @@ static int mpc8xxx_spi_xfer(struct udevice *dev, uint bitlen,
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.
@@ -228,9 +204,7 @@ static int mpc8xxx_spi_xfer(struct udevice *dev, uint bitlen,
static int mpc8xxx_spi_set_speed(struct udevice *dev, uint speed)
{
- struct mpc8xxx_priv *priv = dev_get_priv(dev);
-
- return __spi_set_speed(priv->spi, speed);
+ return 0;
}
static int mpc8xxx_spi_set_mode(struct udevice *dev, uint mode)