imx: mx7ulp: Add soc level initialization codes and functions

Implement soc level functions to get cpu rev, reset cause, enable cache,
etc. We will disable the wdog and init clocks in s_init at very early u-boot
phase.

Since the we are seeking the way to get chip id for mx7ulp, the get_cpu_rev
is hard coded to a fixed value. This may change in future.

Reuse some code in imx-common.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>

arch/arm/Makefile

@@ -99,7 +99,7 @@ ifneq (,$(CONFIG_MX23)$(CONFIG_MX28)$(CONFIG_MX35)$(filter $(SOC), mx25 mx5 mx6
 libs-y += arch/arm/imx-common/
 endif
 else
-ifneq (,$(filter $(SOC), mx25 mx27 mx5 mx6 mx7 mx31 mx35 mxs vf610))
+ifneq (,$(filter $(SOC), mx25 mx27 mx5 mx6 mx7 mx7ulp mx31 mx35 mxs vf610))
 libs-y += arch/arm/imx-common/
 endif
 endif

arch/arm/cpu/armv7/mx7ulp/Makefile

@@ -5,4 +5,4 @@
 #
 #
 
-obj-y	:= clock.o iomux.o pcc.o scg.o
+obj-y	:= soc.o clock.o iomux.o pcc.o scg.o

arch/arm/cpu/armv7/mx7ulp/soc.c

@@ -0,0 +1,239 @@
+/*
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/sys_proto.h>
+
+static char *get_reset_cause(char *);
+
+u32 get_cpu_rev(void)
+{
+	/* Temporally hard code the CPU rev to 0x73, rev 1.0. Fix it later */
+	return (MXC_CPU_MX7ULP << 12) | (1 << 4);
+}
+
+#ifdef CONFIG_REVISION_TAG
+u32 __weak get_board_rev(void)
+{
+	return get_cpu_rev();
+}
+#endif
+
+enum bt_mode get_boot_mode(void)
+{
+	u32 bt0_cfg = 0;
+
+	bt0_cfg = readl(CMC0_RBASE + 0x40);
+	bt0_cfg &= (BT0CFG_LPBOOT_MASK | BT0CFG_DUALBOOT_MASK);
+
+	if (!(bt0_cfg & BT0CFG_LPBOOT_MASK)) {
+		/* No low power boot */
+		if (bt0_cfg & BT0CFG_DUALBOOT_MASK)
+			return DUAL_BOOT;
+		else
+			return SINGLE_BOOT;
+	}
+
+	return LOW_POWER_BOOT;
+}
+
+int arch_cpu_init(void)
+{
+	return 0;
+}
+
+#ifdef CONFIG_BOARD_POSTCLK_INIT
+int board_postclk_init(void)
+{
+	return 0;
+}
+#endif
+
+#define UNLOCK_WORD0 0xC520 /* 1st unlock word */
+#define UNLOCK_WORD1 0xD928 /* 2nd unlock word */
+#define REFRESH_WORD0 0xA602 /* 1st refresh word */
+#define REFRESH_WORD1 0xB480 /* 2nd refresh word */
+
+static void disable_wdog(u32 wdog_base)
+{
+	writel(UNLOCK_WORD0, (wdog_base + 0x04));
+	writel(UNLOCK_WORD1, (wdog_base + 0x04));
+	writel(0x0, (wdog_base + 0x0C)); /* Set WIN to 0 */
+	writel(0x400, (wdog_base + 0x08)); /* Set timeout to default 0x400 */
+	writel(0x120, (wdog_base + 0x00)); /* Disable it and set update */
+
+	writel(REFRESH_WORD0, (wdog_base + 0x04)); /* Refresh the CNT */
+	writel(REFRESH_WORD1, (wdog_base + 0x04));
+}
+
+void init_wdog(void)
+{
+	/*
+	 * ROM will configure WDOG1, disable it or enable it
+	 * depending on FUSE. The update bit is set for reconfigurable.
+	 * We have to use unlock sequence to reconfigure it.
+	 * WDOG2 is not touched by ROM, so it will have default value
+	 * which is enabled. We can directly configure it.
+	 * To simplify the codes, we still use same reconfigure
+	 * process as WDOG1. Because the update bit is not set for
+	 * WDOG2, the unlock sequence won't take effect really.
+	 * It actually directly configure the wdog.
+	 * In this function, we will disable both WDOG1 and WDOG2,
+	 * and set update bit for both. So that kernel can reconfigure them.
+	 */
+	disable_wdog(WDG1_RBASE);
+	disable_wdog(WDG2_RBASE);
+}
+
+
+void s_init(void)
+{
+	/* Disable wdog */
+	init_wdog();
+
+	/* clock configuration. */
+	clock_init();
+
+	return;
+}
+
+#ifndef CONFIG_ULP_WATCHDOG
+void reset_cpu(ulong addr)
+{
+	setbits_le32(SIM0_RBASE, SIM_SOPT1_A7_SW_RESET);
+	while (1)
+		;
+}
+#endif
+
+#if defined(CONFIG_DISPLAY_CPUINFO)
+const char *get_imx_type(u32 imxtype)
+{
+	return "7ULP";
+}
+
+int print_cpuinfo(void)
+{
+	u32 cpurev;
+	char cause[18];
+
+	cpurev = get_cpu_rev();
+
+	printf("CPU:   Freescale i.MX%s rev%d.%d at %d MHz\n",
+	       get_imx_type((cpurev & 0xFF000) >> 12),
+	       (cpurev & 0x000F0) >> 4, (cpurev & 0x0000F) >> 0,
+	       mxc_get_clock(MXC_ARM_CLK) / 1000000);
+
+	printf("Reset cause: %s\n", get_reset_cause(cause));
+
+	printf("Boot mode: ");
+	switch (get_boot_mode()) {
+	case LOW_POWER_BOOT:
+		printf("Low power boot\n");
+		break;
+	case DUAL_BOOT:
+		printf("Dual boot\n");
+		break;
+	case SINGLE_BOOT:
+	default:
+		printf("Single boot\n");
+		break;
+	}
+
+	return 0;
+}
+#endif
+
+#define CMC_SRS_TAMPER                    (1 << 31)
+#define CMC_SRS_SECURITY                  (1 << 30)
+#define CMC_SRS_TZWDG                     (1 << 29)
+#define CMC_SRS_JTAG_RST                  (1 << 28)
+#define CMC_SRS_CORE1                     (1 << 16)
+#define CMC_SRS_LOCKUP                    (1 << 15)
+#define CMC_SRS_SW                        (1 << 14)
+#define CMC_SRS_WDG                       (1 << 13)
+#define CMC_SRS_PIN_RESET                 (1 << 8)
+#define CMC_SRS_WARM                      (1 << 4)
+#define CMC_SRS_HVD                       (1 << 3)
+#define CMC_SRS_LVD                       (1 << 2)
+#define CMC_SRS_POR                       (1 << 1)
+#define CMC_SRS_WUP                       (1 << 0)
+
+static u32 reset_cause = -1;
+
+static char *get_reset_cause(char *ret)
+{
+	u32 cause1, cause = 0, srs = 0;
+	u32 *reg_ssrs = (u32 *)(SRC_BASE_ADDR + 0x28);
+	u32 *reg_srs = (u32 *)(SRC_BASE_ADDR + 0x20);
+
+	if (!ret)
+		return "null";
+
+	srs = readl(reg_srs);
+	cause1 = readl(reg_ssrs);
+	writel(cause1, reg_ssrs);
+
+	reset_cause = cause1;
+
+	cause = cause1 & (CMC_SRS_POR | CMC_SRS_WUP | CMC_SRS_WARM);
+
+	switch (cause) {
+	case CMC_SRS_POR:
+		sprintf(ret, "%s", "POR");
+		break;
+	case CMC_SRS_WUP:
+		sprintf(ret, "%s", "WUP");
+		break;
+	case CMC_SRS_WARM:
+		cause = cause1 & (CMC_SRS_WDG | CMC_SRS_SW |
+			CMC_SRS_JTAG_RST);
+		switch (cause) {
+		case CMC_SRS_WDG:
+			sprintf(ret, "%s", "WARM-WDG");
+			break;
+		case CMC_SRS_SW:
+			sprintf(ret, "%s", "WARM-SW");
+			break;
+		case CMC_SRS_JTAG_RST:
+			sprintf(ret, "%s", "WARM-JTAG");
+			break;
+		default:
+			sprintf(ret, "%s", "WARM-UNKN");
+			break;
+		}
+		break;
+	default:
+		sprintf(ret, "%s-%X", "UNKN", cause1);
+		break;
+	}
+
+	debug("[%X] SRS[%X] %X - ", cause1, srs, srs^cause1);
+	return ret;
+}
+
+#ifdef CONFIG_ENV_IS_IN_MMC
+__weak int board_mmc_get_env_dev(int devno)
+{
+	return CONFIG_SYS_MMC_ENV_DEV;
+}
+
+int mmc_get_env_dev(void)
+{
+	int devno = 0;
+	u32 bt1_cfg = 0;
+
+	/* If not boot from sd/mmc, use default value */
+	if (get_boot_mode() == LOW_POWER_BOOT)
+		return CONFIG_SYS_MMC_ENV_DEV;
+
+	bt1_cfg = readl(CMC1_RBASE + 0x40);
+	devno = (bt1_cfg >> 9) & 0x7;
+
+	return board_mmc_get_env_dev(devno);
+}
+#endif

arch/arm/imx-common/Makefile

@@ -31,6 +31,10 @@ obj-$(CONFIG_IMX_RDC) += rdc-sema.o
 obj-$(CONFIG_IMX_BOOTAUX) += imx_bootaux.o
 obj-$(CONFIG_SECURE_BOOT)    += hab.o
 endif
+ifeq ($(SOC),$(filter $(SOC),mx7ulp))
+obj-y  += cache.o
+obj-$(CONFIG_SECURE_BOOT) += hab.o
+endif
 ifeq ($(SOC),$(filter $(SOC),vf610))
 obj-y += ddrmc-vf610.o
 endif

arch/arm/include/asm/arch-imx/cpu.h

@@ -25,10 +25,12 @@
 #define MXC_CPU_MX6QP		0x69
 #define MXC_CPU_MX7S		0x71 /* dummy ID */
 #define MXC_CPU_MX7D		0x72
+#define MXC_CPU_MX7ULP		0x81 /* Temporally hard code */
 #define MXC_CPU_VF610		0xF6 /* dummy ID */
 
 #define MXC_SOC_MX6		0x60
 #define MXC_SOC_MX7		0x70
+#define MXC_SOC_MX7ULP		0x80 /* dummy */
 
 #define CHIP_REV_1_0            0x10
 #define CHIP_REV_1_1            0x11

arch/arm/include/asm/arch-mx7ulp/sys_proto.h

@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _SYS_PROTO_MX7ULP_H_
+#define _SYS_PROTO_MX7ULP_H_
+
+#include <asm/imx-common/sys_proto.h>
+
+#define BT0CFG_LPBOOT_MASK 0x1
+#define BT0CFG_DUALBOOT_MASK 0x2
+
+enum bt_mode {
+	LOW_POWER_BOOT,		/* LP_BT = 1 */
+	DUAL_BOOT,		/* LP_BT = 0, DUAL_BT = 1 */
+	SINGLE_BOOT		/* LP_BT = 0, DUAL_BT = 0 */
+};
+
+#endif