spi: mpc8xx: Set up speed as requested

Set the speed requested through mpc8xx_spi_set_speed() instead
of hardcoding a fixed speed.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>

diff --git a/drivers/spi/mpc8xx_spi.c b/drivers/spi/mpc8xx_spi.c
index b1abfbf4fcf8fb0d1ffd88393c4ddf9c36634e15..e1448cc6196956281f3e72305e90ee98bf5079b8 100644 (file)
--- a/drivers/spi/mpc8xx_spi.c
+++ b/drivers/spi/mpc8xx_spi.c
@@ -48,6 +48,21 @@ static int mpc8xx_spi_set_mode(struct udevice *dev, uint mod)
 
 static int mpc8xx_spi_set_speed(struct udevice *dev, uint speed)
 {
+       immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
+       cpm8xx_t __iomem *cp = &immr->im_cpm;
+       u8 pm = (gd->arch.brg_clk - 1) / (speed * 16);
+
+       if (pm > 16) {
+               setbits_be16(&cp->cp_spmode, SPMODE_DIV16);
+               pm /= 16;
+               if (pm > 16)
+                       pm = 16;
+       } else {
+               clrbits_be16(&cp->cp_spmode, SPMODE_DIV16);
+       }
+
+       clrsetbits_be16(&cp->cp_spmode, SPMODE_PM(0xf), SPMODE_PM(pm));
+
        return 0;
 }
 
@@ -189,8 +204,8 @@ static int mpc8xx_spi_xfer_one(struct udevice *dev, size_t count,
        out_be16(&rbdf->cbd_sc, BD_SC_EMPTY | BD_SC_WRAP);
        out_be16(&rbdf->cbd_datlen, 0);  /* rx length has no significance */
 
-       clrsetbits_be16(&cp->cp_spmode, ~SPMODE_LOOP, SPMODE_REV | SPMODE_MSTR |
-                       SPMODE_EN | spmode_len | SPMODE_PM(0x8));
+       clrsetbits_be16(&cp->cp_spmode, ~(SPMODE_LOOP | SPMODE_PM(0xf) | SPMODE_DIV16),
+                       SPMODE_REV | SPMODE_MSTR | SPMODE_EN | spmode_len);
        out_8(&cp->cp_spim, 0);         /* Mask  all SPI events */
        out_8(&cp->cp_spie, SPI_EMASK); /* Clear all SPI events */