powerpc/83xx: Add eSDHC support for MPC837xE-RDB/WLAN boards

Actually, the support is already there, but it requires newer U-Boots
(to fill-in clock-frequency, and setup pin multiplexing).

Though, it appears that on RDB boards USBB pins aren't multiplexed
between USB and eSDHC (unlike MDS boards, where USB and eSDHC share
pctl and pwrfault pins).

So, for RDB boards we can safely setup pinmux and manually fill-in
clock-frequency, thus making eSDHC work even with older u-boots.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/83xx/mpc837x_rdb.c b/arch/powerpc/platforms/83xx/mpc837x_rdb.c
index 91d19ab3a794..a1908d261240 100644
--- a/arch/powerpc/platforms/83xx/mpc837x_rdb.c
+++ b/arch/powerpc/platforms/83xx/mpc837x_rdb.c
@@ -17,10 +17,32 @@
 #include <asm/time.h>
 #include <asm/ipic.h>
 #include <asm/udbg.h>
+#include <sysdev/fsl_soc.h>
 #include <sysdev/fsl_pci.h>
 
 #include "mpc83xx.h"
 
+static void mpc837x_rdb_sd_cfg(void)
+{
+	void __iomem *im;
+
+	im = ioremap(get_immrbase(), 0x1000);
+	if (!im) {
+		WARN_ON(1);
+		return;
+	}
+
+	/*
+	 * On RDB boards (in contrast to MDS) USBB pins are used for SD only,
+	 * so we can safely mux them away from the USB block.
+	 */
+	clrsetbits_be32(im + MPC83XX_SICRL_OFFS, MPC837X_SICRL_USBB_MASK,
+						 MPC837X_SICRL_SD);
+	clrsetbits_be32(im + MPC83XX_SICRH_OFFS, MPC837X_SICRH_SPI_MASK,
+						 MPC837X_SICRH_SD);
+	iounmap(im);
+}
+
 /* ************************************************************************
  *
  * Setup the architecture
@@ -42,6 +64,7 @@ static void __init mpc837x_rdb_setup_arch(void)
 		mpc83xx_add_bridge(np);
 #endif
 	mpc837x_usb_cfg();
+	mpc837x_rdb_sd_cfg();
 }
 
 static struct of_device_id mpc837x_ids[] = {