Patchwork [U-Boot,V7,04/10] EXYNOS5: DWMMC: Added FDT support for DWMMC

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Submitter Amar
Date March 5, 2013, 1:11 p.m.
Message ID <1362489090-7745-5-git-send-email-amarendra.xt@samsung.com>
Download mbox | patch
Permalink /patch/225011/
State Changes Requested
Delegated to: Minkyu Kang
Headers show

Comments

Amar - March 5, 2013, 1:11 p.m.
This patch adds FDT support for DWMMC, by reading the DWMMC node data
from the device tree and initialising DWMMC channels as per data
obtained from the node.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Signed-off-by: Amar <amarendra.xt@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
---
Changes since V1:
	1)Updated code to have same signature for the function
	exynos_dwmci_init() for both FDT and non-FDT versions.
	2)Updated code to pass device_id parameter to the function
	exynos5_mmc_set_clk_div() instead of index.
	3)Updated code to decode the value of "samsung,width" from FDT.
	4)Channel index is computed instead of getting from FDT.

Changes since V2:
	1)Updation of commit message and resubmition of proper patch set.

Changes since V3:
	1)Replaced the new function exynos5_mmc_set_clk_div() with the
	existing function set_mmc_clk(). set_mmc_clk() will do the purpose.
	2)Computation of FSYS block clock divisor (pre-ratio) is added.

Changes since V4:
	1)Replaced "unsigned int exynos_dwmmc_init(int index, int bus_width)" with
	int exynos_dwmci_add_port(int, u32, inth, u32)
		i)exynos_dwmmc_add_port() will be used by non-FDT boards.
		ii)In FDT case, exynos_dwmmc_init(const void *blob) will use
		exynos_dwmmc_add_port() for every channel enabled in device node.
	2)Changed the computation method of mmc clock divisor.
	3)Updated exynos_dwmmc_init() to compute the 'clksel_val' within the function.

Changes since V5:
	1)Updated in response to review comments and changed the mmc clock value
	from 50MHz to 52MHz.

Changes since V6:
	No change.

 arch/arm/include/asm/arch-exynos/dwmmc.h |  11 +--
 drivers/mmc/exynos_dw_mmc.c              | 127 ++++++++++++++++++++++++++++---
 include/dwmmc.h                          |   3 +
 3 files changed, 124 insertions(+), 17 deletions(-)

Patch

diff --git a/arch/arm/include/asm/arch-exynos/dwmmc.h b/arch/arm/include/asm/arch-exynos/dwmmc.h
index 8acdf9b..3b147b8 100644
--- a/arch/arm/include/asm/arch-exynos/dwmmc.h
+++ b/arch/arm/include/asm/arch-exynos/dwmmc.h
@@ -27,10 +27,7 @@ 
 #define DWMCI_SET_DRV_CLK(x)	((x) << 16)
 #define DWMCI_SET_DIV_RATIO(x)	((x) << 24)
 
-int exynos_dwmci_init(u32 regbase, int bus_width, int index);
-
-static inline unsigned int exynos_dwmmc_init(int index, int bus_width)
-{
-	unsigned int base = samsung_get_base_mmc() + (0x10000 * index);
-	return exynos_dwmci_init(base, bus_width, index);
-}
+#ifdef CONFIG_OF_CONTROL
+int exynos_dwmmc_init(const void *blob);
+#endif
+int exynos_dwmci_add_port(int index, u32 regbase, int bus_width, u32 clksel);
diff --git a/drivers/mmc/exynos_dw_mmc.c b/drivers/mmc/exynos_dw_mmc.c
index 72a31b7..4238dd9 100644
--- a/drivers/mmc/exynos_dw_mmc.c
+++ b/drivers/mmc/exynos_dw_mmc.c
@@ -19,39 +19,146 @@ 
  */
 
 #include <common.h>
-#include <malloc.h>
 #include <dwmmc.h>
+#include <fdtdec.h>
+#include <libfdt.h>
+#include <malloc.h>
 #include <asm/arch/dwmmc.h>
 #include <asm/arch/clk.h>
+#include <asm/arch/pinmux.h>
 
-static char *EXYNOS_NAME = "EXYNOS DWMMC";
+#define	DWMMC_MAX_CH_NUM		4
+#define	DWMMC_MAX_FREQ			52000000
+#define	DWMMC_MIN_FREQ			400000
+#define	DWMMC_MMC0_CLKSEL_VAL		0x03030001
+#define	DWMMC_MMC2_CLKSEL_VAL		0x03020001
 
+/*
+ * Function used as callback function to initialise the
+ * CLKSEL register for every mmc channel.
+ */
 static void exynos_dwmci_clksel(struct dwmci_host *host)
 {
-	u32 val;
-	val = DWMCI_SET_SAMPLE_CLK(DWMCI_SHIFT_0) |
-		DWMCI_SET_DRV_CLK(DWMCI_SHIFT_0) | DWMCI_SET_DIV_RATIO(0);
+	dwmci_writel(host, DWMCI_CLKSEL, host->clksel_val);
+}
 
-	dwmci_writel(host, DWMCI_CLKSEL, val);
+unsigned int exynos_dwmci_get_clk(int dev_index)
+{
+	return get_mmc_clk(dev_index);
 }
 
-int exynos_dwmci_init(u32 regbase, int bus_width, int index)
+/*
+ * This function adds the mmc channel to be registered with mmc core.
+ * index -	mmc channel number.
+ * regbase -	register base address of mmc channel specified in 'index'.
+ * bus_width -	operating bus width of mmc channel specified in 'index'.
+ * clksel -	value to be written into CLKSEL register in case of FDT.
+ *		NULL in case od non-FDT.
+ */
+int exynos_dwmci_add_port(int index, u32 regbase, int bus_width, u32 clksel)
 {
 	struct dwmci_host *host = NULL;
+	unsigned int div;
+	unsigned long freq, sclk;
 	host = malloc(sizeof(struct dwmci_host));
 	if (!host) {
 		printf("dwmci_host malloc fail!\n");
 		return 1;
 	}
+	/* request mmc clock vlaue of 52MHz.  */
+	freq = 52000000;
+	sclk = get_mmc_clk(index);
+	div = DIV_ROUND_UP(sclk, freq);
+	/* set the clock divisor for mmc */
+	set_mmc_clk(index, div);
 
-	host->name = EXYNOS_NAME;
+	host->name = "EXYNOS DWMMC";
 	host->ioaddr = (void *)regbase;
 	host->buswidth = bus_width;
+
+	if (clksel) {
+		host->clksel_val = clksel;
+	} else {
+		if (0 == index)
+			host->clksel_val = DWMMC_MMC0_CLKSEL_VAL;
+		if (2 == index)
+			host->clksel_val = DWMMC_MMC2_CLKSEL_VAL;
+	}
+
 	host->clksel = exynos_dwmci_clksel;
 	host->dev_index = index;
+	host->mmc_clk = exynos_dwmci_get_clk;
+	/* Add the mmc channel to be registered with mmc core */
+	if (add_dwmci(host, DWMMC_MAX_FREQ, DWMMC_MIN_FREQ)) {
+		debug("dwmmc%d registration failed\n", index);
+		return -1;
+	}
+	return 0;
+}
+
+#ifdef CONFIG_OF_CONTROL
+int exynos_dwmmc_init(const void *blob)
+{
+	int index, bus_width;
+	int node_list[DWMMC_MAX_CH_NUM];
+	int err = 0, dev_id, flag, count, i;
+	u32 clksel_val, base, timing[3];
+
+	count = fdtdec_find_aliases_for_id(blob, "mmc",
+				COMPAT_SAMSUNG_EXYNOS5_DWMMC, node_list,
+				DWMMC_MAX_CH_NUM);
+
+	for (i = 0; i < count; i++) {
+		int node = node_list[i];
+
+		if (node <= 0)
+			continue;
 
-	add_dwmci(host, 52000000, 400000);
+		/* Extract device id for each mmc channel */
+		dev_id = pinmux_decode_periph_id(blob, node);
 
+		/* Get the bus width from the device node */
+		bus_width = fdtdec_get_int(blob, node, "samsung,bus-width", 0);
+		if (bus_width <= 0) {
+			debug("DWMMC: Can't get bus-width\n");
+			return -1;
+		}
+		if (8 == bus_width)
+			flag = PINMUX_FLAG_8BIT_MODE;
+		else
+			flag = PINMUX_FLAG_NONE;
+
+		/* config pinmux for each mmc channel */
+		err = exynos_pinmux_config(dev_id, flag);
+		if (err) {
+			debug("DWMMC not configured\n");
+			return err;
+		}
+
+		index = dev_id - PERIPH_ID_SDMMC0;
+
+		/* Get the base address from the device node */
+		base = fdtdec_get_addr(blob, node, "reg");
+		if (!base) {
+			debug("DWMMC: Can't get base address\n");
+			return -1;
+		}
+		/* Extract the timing info from the node */
+		err = fdtdec_get_int_array(blob, node, "samsung,timing",
+					timing, 3);
+		if (err) {
+			debug("Can't get sdr-timings for divider\n");
+			return -1;
+		}
+
+		clksel_val = (DWMCI_SET_SAMPLE_CLK(timing[0]) |
+				DWMCI_SET_DRV_CLK(timing[1]) |
+				DWMCI_SET_DIV_RATIO(timing[2]));
+		/* Initialise each mmc channel */
+		err = exynos_dwmci_add_port(index, base, bus_width, clksel_val);
+		if (err)
+			debug("dwmmc Channel-%d init failed\n", index);
+	}
 	return 0;
 }
-
+#endif
diff --git a/include/dwmmc.h b/include/dwmmc.h
index c8b1d40..e142f3e 100644
--- a/include/dwmmc.h
+++ b/include/dwmmc.h
@@ -123,6 +123,8 @@ 
 #define MSIZE(x)		((x) << 28)
 #define RX_WMARK(x)		((x) << 16)
 #define TX_WMARK(x)		(x)
+#define RX_WMARK_SHIFT		16
+#define RX_WMARK_MASK		(0xfff << RX_WMARK_SHIFT)
 
 #define DWMCI_IDMAC_OWN		(1 << 31)
 #define DWMCI_IDMAC_CH		(1 << 4)
@@ -144,6 +146,7 @@  struct dwmci_host {
 	unsigned int bus_hz;
 	int dev_index;
 	int buswidth;
+	u32 clksel_val;
 	u32 fifoth_val;
 	struct mmc *mmc;