mmc: sh_sdhi: Add 64-bit access to sd_buf support

Renesas SDHI SD/MMC driver has 16-bit width bus access to SD_BUF.
This adds 64-bit width bus access to SD_BUF.

Signed-off-by: Kouei Abe <kouei.abe.cp@renesas.com>
Cc: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@renesas.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Cc: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
diff --git a/arch/arm/mach-rmobile/include/mach/sh_sdhi.h b/arch/arm/mach-rmobile/include/mach/sh_sdhi.h
index 057bf3f..a5ea45b 100644
--- a/arch/arm/mach-rmobile/include/mach/sh_sdhi.h
+++ b/arch/arm/mach-rmobile/include/mach/sh_sdhi.h
@@ -1,9 +1,9 @@
 /*
  * drivers/mmc/sh-sdhi.h
  *
- * SD/MMC driver for Reneas rmobile ARM SoCs
+ * SD/MMC driver for Renesas rmobile ARM SoCs
  *
- * Copyright (C) 2013-2014 Renesas Electronics Corporation
+ * Copyright (C) 2013-2017 Renesas Electronics Corporation
  * Copyright (C) 2008-2009 Renesas Solutions Corp.
  *
  * SPDX-License-Identifier:	GPL-2.0
@@ -162,7 +162,9 @@
 #define	CLKDEV_INIT			400000		/* 100 - 400 KHz */
 
 /* For quirk */
-#define SH_SDHI_QUIRK_16BIT_BUF		(1)
+#define SH_SDHI_QUIRK_16BIT_BUF		BIT(0)
+#define SH_SDHI_QUIRK_64BIT_BUF		BIT(1)
+
 int sh_sdhi_init(unsigned long addr, int ch, unsigned long quirks);
 
 #endif /* _SH_SDHI_H */
diff --git a/drivers/mmc/sh_sdhi.c b/drivers/mmc/sh_sdhi.c
index 7f0b4c2..d1dd0f0 100644
--- a/drivers/mmc/sh_sdhi.c
+++ b/drivers/mmc/sh_sdhi.c
@@ -3,7 +3,7 @@
  *
  * SD/MMC driver for Renesas rmobile ARM SoCs.
  *
- * Copyright (C) 2011,2013-2014 Renesas Electronics Corporation
+ * Copyright (C) 2011,2013-2017 Renesas Electronics Corporation
  * Copyright (C) 2014 Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
  * Copyright (C) 2008-2009 Renesas Solutions Corp.
  *
@@ -29,6 +29,17 @@
 	unsigned char sd_error;
 	unsigned char detect_waiting;
 };
+
+static inline void sh_sdhi_writeq(struct sh_sdhi_host *host, int reg, u64 val)
+{
+	writeq(val, host->addr + (reg << host->bus_shift));
+}
+
+static inline u64 sh_sdhi_readq(struct sh_sdhi_host *host, int reg)
+{
+	return readq(host->addr + (reg << host->bus_shift));
+}
+
 static inline void sh_sdhi_writew(struct sh_sdhi_host *host, int reg, u16 val)
 {
 	writew(val, host->addr + (reg << host->bus_shift));
@@ -261,6 +272,7 @@
 	long time;
 	unsigned short blocksize, i;
 	unsigned short *p = (unsigned short *)data->dest;
+	u64 *q = (u64 *)data->dest;
 
 	if ((unsigned long)p & 0x00000001) {
 		debug(DRIVER_NAME": %s: The data pointer is unaligned.",
@@ -281,8 +293,12 @@
 
 	host->wait_int = 0;
 	blocksize = sh_sdhi_readw(host, SDHI_SIZE);
-	for (i = 0; i < blocksize / 2; i++)
-		*p++ = sh_sdhi_readw(host, SDHI_BUF0);
+	if (host->quirks & SH_SDHI_QUIRK_64BIT_BUF)
+		for (i = 0; i < blocksize / 8; i++)
+			*q++ = sh_sdhi_readq(host, SDHI_BUF0);
+	else
+		for (i = 0; i < blocksize / 2; i++)
+			*p++ = sh_sdhi_readw(host, SDHI_BUF0);
 
 	time = sh_sdhi_wait_interrupt_flag(host);
 	if (time == 0 || host->sd_error != 0)
@@ -297,6 +313,7 @@
 	long time;
 	unsigned short blocksize, i, sec;
 	unsigned short *p = (unsigned short *)data->dest;
+	u64 *q = (u64 *)data->dest;
 
 	if ((unsigned long)p & 0x00000001) {
 		debug(DRIVER_NAME": %s: The data pointer is unaligned.",
@@ -319,8 +336,12 @@
 
 		host->wait_int = 0;
 		blocksize = sh_sdhi_readw(host, SDHI_SIZE);
-		for (i = 0; i < blocksize / 2; i++)
-			*p++ = sh_sdhi_readw(host, SDHI_BUF0);
+		if (host->quirks & SH_SDHI_QUIRK_64BIT_BUF)
+			for (i = 0; i < blocksize / 8; i++)
+				*q++ = sh_sdhi_readq(host, SDHI_BUF0);
+		else
+			for (i = 0; i < blocksize / 2; i++)
+				*p++ = sh_sdhi_readw(host, SDHI_BUF0);
 	}
 
 	return 0;
@@ -332,6 +353,7 @@
 	long time;
 	unsigned short blocksize, i;
 	const unsigned short *p = (const unsigned short *)data->src;
+	const u64 *q = (const u64 *)data->src;
 
 	if ((unsigned long)p & 0x00000001) {
 		debug(DRIVER_NAME": %s: The data pointer is unaligned.",
@@ -356,8 +378,12 @@
 
 	host->wait_int = 0;
 	blocksize = sh_sdhi_readw(host, SDHI_SIZE);
-	for (i = 0; i < blocksize / 2; i++)
-		sh_sdhi_writew(host, SDHI_BUF0, *p++);
+	if (host->quirks & SH_SDHI_QUIRK_64BIT_BUF)
+		for (i = 0; i < blocksize / 8; i++)
+			sh_sdhi_writeq(host, SDHI_BUF0, *q++);
+	else
+		for (i = 0; i < blocksize / 2; i++)
+			sh_sdhi_writew(host, SDHI_BUF0, *p++);
 
 	time = sh_sdhi_wait_interrupt_flag(host);
 	if (time == 0 || host->sd_error != 0)
@@ -372,6 +398,7 @@
 	long time;
 	unsigned short i, sec, blocksize;
 	const unsigned short *p = (const unsigned short *)data->src;
+	const u64 *q = (const u64 *)data->src;
 
 	debug("%s: blocks = %d, blocksize = %d\n",
 	      __func__, data->blocks, data->blocksize);
@@ -388,8 +415,12 @@
 
 		host->wait_int = 0;
 		blocksize = sh_sdhi_readw(host, SDHI_SIZE);
-		for (i = 0; i < blocksize / 2; i++)
-			sh_sdhi_writew(host, SDHI_BUF0, *p++);
+		if (host->quirks & SH_SDHI_QUIRK_64BIT_BUF)
+			for (i = 0; i < blocksize / 8; i++)
+				sh_sdhi_writeq(host, SDHI_BUF0, *q++);
+		else
+			for (i = 0; i < blocksize / 2; i++)
+				sh_sdhi_writew(host, SDHI_BUF0, *p++);
 	}
 
 	return 0;
@@ -687,7 +718,9 @@
 	host->addr = addr;
 	host->quirks = quirks;
 
-	if (host->quirks & SH_SDHI_QUIRK_16BIT_BUF)
+	if (host->quirks & SH_SDHI_QUIRK_64BIT_BUF)
+		host->bus_shift = 2;
+	else if (host->quirks & SH_SDHI_QUIRK_16BIT_BUF)
 		host->bus_shift = 1;
 
 	return ret;