zephyr: add npcx-specific system functions for external storage.

In order to sysjump we first need to copy the RW image from flash.
rom_chip.h adds a macro to call ROM function download_from_flash
(while system_external_storage.c contains all the npcx specific code
needed to perform the sysjump).

BRANCH=none
BUG=b:167392037
TEST=zmake testall

Signed-off-by: Yuval Peress <peress@chromium.org>
Change-Id: I762954a71e87036b63513ae8b400605ed507fcf6
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2693527
Reviewed-by: Simon Glass <sjg@chromium.org>

3 files changed, 201 insertions, 0 deletions

diff --git a/zephyr/shim/chip/npcx/CMakeLists.txt b/zephyr/shim/chip/npcx/CMakeLists.txt
index e5c16b7144..3c841da1fe 100644
--- a/zephyr/shim/chip/npcx/CMakeLists.txt
+++ b/zephyr/shim/chip/npcx/CMakeLists.txt
@@ -7,3 +7,6 @@ zephyr_include_directories(include)
 zephyr_sources(clock.c)
 zephyr_sources_ifdef(CONFIG_CROS_KB_RAW_NPCX  keyboard_raw.c)
 zephyr_sources_ifdef(CONFIG_CROS_EC           system.c)
+
+zephyr_sources_ifdef(CONFIG_PLATFORM_EC_EXTERNAL_STORAGE
+        system_external_storage.c)
diff --git a/zephyr/shim/chip/npcx/include/rom_chip.h b/zephyr/shim/chip/npcx/include/rom_chip.h
new file mode 100644
index 0000000000..aab166e6f1
--- /dev/null
+++ b/zephyr/shim/chip/npcx/include/rom_chip.h
@@ -0,0 +1,57 @@
+/* Copyright 2021 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef __CROS_EC_ROM_CHIP_H
+#define __CROS_EC_ROM_CHIP_H
+
+#include "common.h"
+
+/* Enumerations of ROM api functions */
+enum API_SIGN_OPTIONS_T {
+	SIGN_NO_CHECK = 0,
+	SIGN_CRC_CHECK = 1,
+};
+
+enum API_RETURN_STATUS_T {
+	/* Successful download */
+	API_RET_STATUS_OK = 0,
+	/* Address is outside of flash or not 4 bytes aligned. */
+	API_RET_STATUS_INVALID_SRC_ADDR = 1,
+	/* Address is outside of RAM or not 4 bytes aligned. */
+	API_RET_STATUS_INVALID_DST_ADDR = 2,
+	/* Size is 0 or not 4 bytes aligned. */
+	API_RET_STATUS_INVALID_SIZE = 3,
+	/* Flash Address + Size is out of flash. */
+	API_RET_STATUS_INVALID_SIZE_OUT_OF_FLASH = 4,
+	/* RAM Address + Size is out of RAM. */
+	API_RET_STATUS_INVALID_SIZE_OUT_OF_RAM = 5,
+	/* Wrong sign option. */
+	API_RET_STATUS_INVALID_SIGN = 6,
+	/* Error during Code copy. */
+	API_RET_STATUS_COPY_FAILED = 7,
+	/* Execution Address is outside of RAM */
+	API_RET_STATUS_INVALID_EXE_ADDR = 8,
+	/* Bad CRC value */
+	API_RET_STATUS_INVALID_SIGNATURE = 9,
+};
+
+/* Macro functions of ROM api functions */
+#define ADDR_DOWNLOAD_FROM_FLASH (*(volatile uint32_t *) 0x40)
+#define download_from_flash(src_offset, dest_addr, size, sign, exe_addr, \
+	status) \
+	(((download_from_flash_ptr) ADDR_DOWNLOAD_FROM_FLASH) \
+	(src_offset, dest_addr, size, sign, exe_addr, status))
+
+/* Declarations of ROM api functions */
+typedef void (*download_from_flash_ptr) (
+	uint32_t src_offset, /* The offset of the data to be downloaded */
+	uint32_t dest_addr,  /* The address of the downloaded data in the RAM*/
+	uint32_t size,       /* Number of bytes to download */
+	enum API_SIGN_OPTIONS_T sign, /* Need CRC check or not */
+	uint32_t exe_addr, /* jump to this address after download if not zero */
+	enum API_RETURN_STATUS_T *status /* Status fo download */
+);
+
+#endif /* __CROS_EC_ROM_CHIP_H */
diff --git a/zephyr/shim/chip/npcx/system_external_storage.c b/zephyr/shim/chip/npcx/system_external_storage.c
new file mode 100644
index 0000000000..873686e44a
--- /dev/null
+++ b/zephyr/shim/chip/npcx/system_external_storage.c
@@ -0,0 +1,141 @@
+/* Copyright 2021 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "clock_chip.h"
+#include "common.h"
+#include "rom_chip.h"
+#include "system.h"
+
+/* TODO (b:179900857) Make this implementation not npcx specific. */
+
+#define NPCX_MDC_BASE_ADDR                0x4000C000
+#define NPCX_FWCTRL                       REG8(NPCX_MDC_BASE_ADDR + 0x007)
+#define NPCX_FWCTRL_RO_REGION             0
+#define NPCX_FWCTRL_FW_SLOT               1
+#define SET_BIT(reg, bit)           ((reg) |= (0x1 << (bit)))
+#define CLEAR_BIT(reg, bit)         ((reg) &= (~(0x1 << (bit))))
+#define IS_BIT_SET(reg, bit)        (((reg) >> (bit)) & (0x1))
+
+void system_jump_to_booter(void)
+{
+	enum API_RETURN_STATUS_T status __attribute__((unused));
+	static uint32_t flash_offset;
+	static uint32_t flash_used;
+	static uint32_t addr_entry;
+
+	/*
+	 * Get memory offset and size for RO/RW regions.
+	 * Both of them need 16-bytes alignment since GDMA burst mode.
+	 */
+	switch (system_get_shrspi_image_copy()) {
+	case EC_IMAGE_RW:
+		flash_offset = CONFIG_EC_WRITABLE_STORAGE_OFF +
+				CONFIG_RW_STORAGE_OFF;
+		flash_used = CONFIG_RW_SIZE;
+		break;
+#ifdef CONFIG_RW_B
+	case EC_IMAGE_RW_B:
+		flash_offset = CONFIG_EC_WRITABLE_STORAGE_OFF +
+				CONFIG_RW_B_STORAGE_OFF;
+		flash_used = CONFIG_RW_SIZE;
+		break;
+#endif
+	case EC_IMAGE_RO:
+	default: /* Jump to RO by default */
+		flash_offset = CONFIG_EC_PROTECTED_STORAGE_OFF +
+				CONFIG_RO_STORAGE_OFF;
+		flash_used = CONFIG_RO_SIZE;
+		break;
+	}
+
+	/* Make sure the reset vector is inside the destination image */
+	addr_entry = *(uintptr_t *)(flash_offset +
+				    CONFIG_MAPPED_STORAGE_BASE + 4);
+
+	/*
+	 * Speed up FW download time by increasing clock freq of EC. It will
+	 * restore to default in clock_init() later.
+	 */
+	clock_turbo();
+
+/*
+ * npcx9 Rev.1 has the problem for download_from_flash API.
+ * Workwaroud it by executing the system_download_from_flash function
+ * in the suspend RAM like npcx5.
+ * TODO: Removing npcx9 when Rev.2 is available.
+ */
+	/* Bypass for GMDA issue of ROM api utilities */
+#if defined(CHIP_FAMILY_NPCX5) || defined(CONFIG_WORKAROUND_FLASH_DOWNLOAD_API)
+	system_download_from_flash(
+		flash_offset,      /* The offset of the data in spi flash */
+		CONFIG_PROGRAM_MEMORY_BASE, /* RAM Addr of downloaded data */
+		flash_used,        /* Number of bytes to download      */
+		addr_entry         /* jump to this address after download */
+	);
+#else
+	download_from_flash(
+		flash_offset,      /* The offset of the data in spi flash */
+		CONFIG_PROGRAM_MEMORY_BASE, /* RAM Addr of downloaded data */
+		flash_used,        /* Number of bytes to download      */
+		SIGN_NO_CHECK,     /* Need CRC check or not               */
+		addr_entry,        /* jump to this address after download */
+		&status            /* Status fo download */
+	);
+#endif
+}
+
+uint32_t system_get_lfw_address()
+{
+	/*
+	 * In A3 version, we don't use little FW anymore
+	 * We provide the alternative function in ROM
+	 */
+	uint32_t jump_addr = (uint32_t)system_jump_to_booter;
+	return jump_addr;
+}
+
+enum ec_image system_get_shrspi_image_copy(void)
+{
+	/* TODO (b:179900857) Make this implementation not npcx specific. */
+	if (IS_BIT_SET(NPCX_FWCTRL, NPCX_FWCTRL_RO_REGION)) {
+		/* RO image */
+#ifdef CHIP_HAS_RO_B
+		if (!IS_BIT_SET(NPCX_FWCTRL, NPCX_FWCTRL_FW_SLOT))
+			return EC_IMAGE_RO_B;
+#endif
+		return EC_IMAGE_RO;
+	} else {
+#ifdef CONFIG_RW_B
+		/* RW image */
+		if (!IS_BIT_SET(NPCX_FWCTRL, NPCX_FWCTRL_FW_SLOT))
+			/* Slot A */
+			return EC_IMAGE_RW_B;
+#endif
+		return EC_IMAGE_RW;
+	}
+}
+
+void system_set_image_copy(enum ec_image copy)
+{
+	/* TODO (b:179900857) Make this implementation not npcx specific. */
+	switch (copy) {
+	case EC_IMAGE_RW:
+		CLEAR_BIT(NPCX_FWCTRL, NPCX_FWCTRL_RO_REGION);
+		SET_BIT(NPCX_FWCTRL, NPCX_FWCTRL_FW_SLOT);
+		break;
+#ifdef CONFIG_RW_B
+	case EC_IMAGE_RW_B:
+		CLEAR_BIT(NPCX_FWCTRL, NPCX_FWCTRL_RO_REGION);
+		CLEAR_BIT(NPCX_FWCTRL, NPCX_FWCTRL_FW_SLOT);
+		break;
+#endif
+	default:
+		/* Fall through to EC_IMAGE_RO */
+	case EC_IMAGE_RO:
+		SET_BIT(NPCX_FWCTRL, NPCX_FWCTRL_RO_REGION);
+		SET_BIT(NPCX_FWCTRL, NPCX_FWCTRL_FW_SLOT);
+		break;
+	}
+}