ARM: uniphier: deassert RST_n of eMMC device for LD11/LD20

For LD11 and LD20 SoCs, the RST_n pin is asserted by default.  If
the EXT_CSD[162], bit[1:0] (RST_n_ENABLE) is fused, the eMMC device
would stay in the reset state until its RST_n pin is deasserted by
software.

Currently, this is cared by an ad-hoc way because the eMMC hardware
reset provider is not supported in U-Boot for now.  This code should
be re-written once the "mmc-pwrseq-emmc" binding is supported.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/arch/arm/mach-uniphier/clk/clk-ld11.c b/arch/arm/mach-uniphier/clk/clk-ld11.c
index b1e82a1..a4dcde7 100644
--- a/arch/arm/mach-uniphier/clk/clk-ld11.c
+++ b/arch/arm/mach-uniphier/clk/clk-ld11.c
@@ -13,6 +13,8 @@
 #include "../sc64-regs.h"
 #include "../sg-regs.h"
 
+#define SDCTRL_EMMC_HW_RESET	0x59810280
+
 void uniphier_ld11_clk_init(void)
 {
 	/* if booted from a device other than USB, without stand-by MPU */
@@ -28,6 +30,9 @@
 		writel(7, SG_ETPHYCNT);
 	}
 
+	/* TODO: use "mmc-pwrseq-emmc" */
+	writel(1, SDCTRL_EMMC_HW_RESET);
+
 #ifdef CONFIG_USB_EHCI
 	{
 		/* FIXME: the current clk driver can not handle parents */