exynos5-dt-types: add board detection for Odroid XU3/XU3L/XU4.

This commit adds additional file with implementation of board
detection code for Odroid-XU3/XU4.

The detection depends on compatible found in fdt:
- "samsung,exynos5" - uses Exynos5 generic code
- "samsung,odroidxu3" - try detect XU3 revision

There are few revisions of Odroid XU3/XU4, each can be detected
by checking the value of channel 9 of built-in ADC:
 Rev   ADC  Board
 0.1     0  XU3 0.1
 0.2   372  XU3 0.2 | XU3L - no DISPLAYPORT
 0.3  1280  XU4 0.1

The detection code depends on the ADC+10% value.

Implementation of functions:
- set_board_type()     - read ADC and set type
- get_board_rev()      - returns board revision: 1..3
- get_board_type()     - returns board type string

Additional functions with return values of bool:
- board_is_generic()   - true if found compatible "samsung,exynos5"
                         but not "samsung,odroidxu3"
- board_is_odroidxu3() - true if found compatible "samsung,odroidxu3"
                         and one of XU3 revision.
- board_is_odroidxu4() - true if found compatible "samsung,odroidxu3"
                         and XU4 revision.

After I2C controller init, the get_board_type() can check
if the XU3 board is a "Lite" variant, by probing chip
0x40 on I2C0 (INA231 - exists only on non-lite).
This is useful for setting fdt file name at misc_init_r().

Enabled configs:
- CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
- CONFIG_ODROID_REV_AIN
- CONFIG_REVISION_TAG
- CONFIG_BOARD_TYPES

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Cc: Minkyu Kang <mk7.kang@samsung.com>
Cc: Simon Glass <sjg@chromium.org>
Tested-by: Anand Moon <linux.amoon@gmail.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>

board/samsung/common/Makefile

@@ -11,5 +11,8 @@ obj-$(CONFIG_MISC_COMMON) += misc.o
 
 ifndef CONFIG_SPL_BUILD
 obj-$(CONFIG_BOARD_COMMON)	+= board.o
-obj-$(CONFIG_EXYNOS5_DT)	+= exynos5-dt.o
+ifdef CONFIG_EXYNOS5_DT
+obj-y += exynos5-dt.o
+obj-$(CONFIG_BOARD_TYPES) += exynos5-dt-types.o
+endif
 endif

board/samsung/common/exynos5-dt-types.c

@@ -0,0 +1,196 @@
+/*
+ * Copyright (C) 2015 Samsung Electronics
+ * Przemyslaw Marczak <p.marczak@samsung.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <adc.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <power/pmic.h>
+#include <power/regulator.h>
+#include <power/s2mps11.h>
+#include <samsung/exynos5-dt-types.h>
+#include <samsung/misc.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static const struct udevice_id board_ids[] = {
+	{ .compatible = "samsung,odroidxu3", .data = EXYNOS5_BOARD_ODROID_XU3 },
+	{ .compatible = "samsung,exynos5", .data = EXYNOS5_BOARD_GENERIC },
+	{ },
+};
+
+/**
+ * Odroix XU3/4 board revisions:
+ * Rev   ADCmax  Board
+ * 0.1     0     XU3 0.1
+ * 0.2   410     XU3 0.2 | XU3L - no DISPLAYPORT (probe I2C0:0x40 / INA231)
+ * 0.3  1408     XU4 0.1
+ * Use +10 % for ADC value tolerance.
+ */
+struct odroid_rev_info odroid_info[] = {
+	{ EXYNOS5_BOARD_ODROID_XU3_REV01, 1, 10, "xu3" },
+	{ EXYNOS5_BOARD_ODROID_XU3_REV02, 2, 410, "xu3" },
+	{ EXYNOS5_BOARD_ODROID_XU4_REV01, 1, 1408, "xu4" },
+	{ EXYNOS5_BOARD_ODROID_UNKNOWN, 0, 4095, "unknown" },
+};
+
+static unsigned int odroid_get_rev(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(odroid_info); i++) {
+		if (odroid_info[i].board_type == gd->board_type)
+			return odroid_info[i].board_rev;
+	}
+
+	return 0;
+}
+
+static int odroid_get_board_type(void)
+{
+	unsigned int adcval;
+	int ret, i;
+
+	ret = adc_channel_single_shot("adc", CONFIG_ODROID_REV_AIN, &adcval);
+	if (ret)
+		goto rev_default;
+
+	for (i = 0; i < ARRAY_SIZE(odroid_info); i++) {
+		/* ADC tolerance: +20 % */
+		if (adcval < odroid_info[i].adc_val)
+			return odroid_info[i].board_type;
+	}
+
+rev_default:
+	return EXYNOS5_BOARD_ODROID_XU3;
+}
+
+/**
+ * odroid_get_type_str - returns pointer to one of the board type string.
+ * Board types: "xu3", "xu3-lite", "xu4". However the "xu3lite" can be
+ * detected only when the i2c controller is ready to use. Fortunately,
+ * XU3 and XU3L are compatible, and the information about board lite
+ * revision is needed before booting the linux, to set proper environment
+ * variable: $fdtfile.
+ */
+static const char *odroid_get_type_str(void)
+{
+	const char *type_xu3l = "xu3-lite";
+	struct udevice *dev, *chip;
+	int i, ret;
+
+	if (gd->board_type != EXYNOS5_BOARD_ODROID_XU3_REV02)
+		goto exit;
+
+	ret = pmic_get("s2mps11", &dev);
+	if (ret)
+		goto exit;
+
+	/* Enable LDO26: 3.0V */
+	ret = pmic_reg_write(dev, S2MPS11_REG_L26CTRL,
+			     S2MPS11_LDO26_ENABLE);
+	if (ret)
+		goto exit;
+
+	/* Check XU3Lite by probe INA231 I2C0:0x40 */
+	ret = uclass_get_device(UCLASS_I2C, 0, &dev);
+	if (ret)
+		goto exit;
+
+	ret = dm_i2c_probe(dev, 0x40, 0x0, &chip);
+	if (ret)
+		return type_xu3l;
+
+exit:
+	for (i = 0; i < ARRAY_SIZE(odroid_info); i++) {
+		if (odroid_info[i].board_type == gd->board_type)
+			return odroid_info[i].name;
+	}
+
+	return NULL;
+}
+
+bool board_is_odroidxu3(void)
+{
+	if (gd->board_type >= EXYNOS5_BOARD_ODROID_XU3 &&
+	    gd->board_type <= EXYNOS5_BOARD_ODROID_XU3_REV02)
+		return true;
+
+	return false;
+}
+
+bool board_is_odroidxu4(void)
+{
+	if (gd->board_type == EXYNOS5_BOARD_ODROID_XU4_REV01)
+		return true;
+
+	return false;
+}
+
+bool board_is_generic(void)
+{
+	if (gd->board_type == EXYNOS5_BOARD_GENERIC)
+		return true;
+
+	return false;
+}
+
+/**
+ * get_board_rev() - return detected board revision.
+ *
+ * @return:  return board revision number for XU3 or 0 for generic
+ */
+u32 get_board_rev(void)
+{
+	if (board_is_generic())
+		return 0;
+
+	return odroid_get_rev();
+}
+
+/**
+ * get_board_type() - returns board type string.
+ *
+ * @return:  return board type string for XU3 or empty string for generic
+ */
+const char *get_board_type(void)
+{
+	const char *generic = "";
+
+	if (board_is_generic())
+		return generic;
+
+	return odroid_get_type_str();
+}
+
+/**
+ * set_board_type() - set board type in gd->board_type.
+ * As default type set EXYNOS5_BOARD_GENERIC, if detect Odroid,
+ * then set its proper type.
+ */
+void set_board_type(void)
+{
+	const struct udevice_id *of_match = board_ids;
+	int ret;
+
+	gd->board_type = EXYNOS5_BOARD_GENERIC;
+
+	while (of_match->compatible) {
+		ret = fdt_node_check_compatible(gd->fdt_blob, 0,
+						of_match->compatible);
+		if (ret)
+			of_match++;
+
+		gd->board_type = of_match->data;
+		break;
+	}
+
+	/* If Odroid, then check its revision */
+	if (board_is_odroidxu3())
+		gd->board_type = odroid_get_board_type();
+}

board/samsung/common/exynos5-dt.c

@@ -27,7 +27,10 @@
 #include <power/pmic.h>
 #include <power/max77686_pmic.h>
 #include <power/regulator.h>
+#include <power/s2mps11.h>
 #include <power/s5m8767.h>
+#include <samsung/exynos5-dt-types.h>
+#include <samsung/misc.h>
 #include <tmu.h>
 
 DECLARE_GLOBAL_DATA_PTR;
@@ -335,15 +338,24 @@ int board_usb_init(int index, enum usb_init_type init)
 #ifdef CONFIG_SET_DFU_ALT_INFO
 char *get_dfu_alt_system(char *interface, char *devstr)
 {
+	char *info = "Not supported!";
+
+	if (board_is_odroidxu4())
+		return info;
+
 	return getenv("dfu_alt_system");
 }
 
 char *get_dfu_alt_boot(char *interface, char *devstr)
 {
+	char *info = "Not supported!";
 	struct mmc *mmc;
 	char *alt_boot;
 	int dev_num;
 
+	if (board_is_odroidxu4())
+		return info;
+
 	dev_num = simple_strtoul(devstr, NULL, 10);
 
 	mmc = find_mmc_device(dev_num);

configs/odroid-xu3_defconfig

@@ -16,3 +16,5 @@ CONFIG_PMIC_S2MPS11=y
 CONFIG_USB=y
 CONFIG_DM_USB=y
 CONFIG_VIDEO_BRIDGE=y
+CONFIG_ADC=y
+CONFIG_ADC_EXYNOS=y

include/configs/odroid_xu3.h

@@ -94,6 +94,8 @@
 	"boot.scr fat 0 1;"                 \
 	"boot.cmd fat 0 1;"                 \
 	"exynos5422-odroidxu3.dtb fat 0 1;" \
+	"exynos5422-odroidxu3-lite.dtb fat 0 1;" \
+	"exynos5422-odroidxu4.dtb fat 0 1;" \
 	"boot part 0 1;"                    \
 	"root part 0 2\0"
 
@@ -113,9 +115,19 @@
 
 /* Enable: board/samsung/common/misc.c to use set_dfu_alt_info() */
 #define CONFIG_MISC_COMMON
+#define CONFIG_MISC_INIT_R
 #define CONFIG_SET_DFU_ALT_INFO
 #define CONFIG_SET_DFU_ALT_BUF_LEN	(SZ_1K)
 
+/* Set soc_rev, soc_id, board_rev, boardname, fdtfile */
+#define CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
+#define CONFIG_ODROID_REV_AIN			9
+#define CONFIG_REVISION_TAG
+#define CONFIG_BOARD_TYPES
+
+#undef CONFIG_SYS_BOARD
+#define CONFIG_SYS_BOARD	"odroid"
+
 /* Define new extra env settings, including DFU settings */
 #undef CONFIG_EXTRA_ENV_SETTINGS
 #define CONFIG_EXTRA_ENV_SETTINGS \

include/samsung/exynos5-dt-types.h

@@ -0,0 +1,27 @@
+#ifndef _EXYNOS5_DT_H_
+#define _EXYNOS5_DT_H_
+
+enum {
+	EXYNOS5_BOARD_GENERIC,
+
+	EXYNOS5_BOARD_ODROID_XU3,
+	EXYNOS5_BOARD_ODROID_XU3_REV01,
+	EXYNOS5_BOARD_ODROID_XU3_REV02,
+	EXYNOS5_BOARD_ODROID_XU4_REV01,
+	EXYNOS5_BOARD_ODROID_UNKNOWN,
+
+	EXYNOS5_BOARD_COUNT,
+};
+
+struct odroid_rev_info {
+	int board_type;
+	int board_rev;
+	int adc_val;
+	const char *name;
+};
+
+bool board_is_generic(void);
+bool board_is_odroidxu3(void);
+bool board_is_odroidxu4(void);
+
+#endif