boot/espressif: Add CMakeLists.txt and mcuboot_config.h

Add sources and headers required for build

Signed-off-by: Shubham Kulkarni <shubham.kulkarni@espressif.com>
diff --git a/boot/espressif/port/esp32/ld/bootloader.ld b/boot/espressif/port/esp32/ld/bootloader.ld
new file mode 100644
index 0000000..87f5c56
--- /dev/null
+++ b/boot/espressif/port/esp32/ld/bootloader.ld
@@ -0,0 +1,135 @@
+/*
+ * Linker file used to link the bootloader.
+ */
+
+MEMORY
+{
+    iram_loader_seg (RWX) : org = 0x4009D000, len = 0x3000
+    iram_seg (RWX) : org = 0x40085000, len = 0x8000
+    dram_seg (RW) : org = 0x3FFF5000, len = 0xB000
+}
+
+ENTRY(main)
+
+SECTIONS
+{
+    .iram_loader.text :
+    {
+        . = ALIGN (16);
+        _loader_text_start = ABSOLUTE(.);
+        *(.stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
+        *(.iram1 .iram1.*) /* catch stray IRAM_ATTR */
+        *libhal.a:bootloader_flash.*(.literal .text .literal.* .text.*)
+        *libhal.a:bootloader_flash_config_esp32.*(.literal .text .literal.* .text.*)
+        *esp_mcuboot.*(.literal .text .literal.* .text.*)
+        *esp_loader.*(.literal .text .literal.* .text.*)
+        *(.fini.literal)
+        *(.fini)
+        *(.gnu.version)
+        _loader_text_end = ABSOLUTE(.);
+    } > iram_loader_seg
+    
+    .iram.text :
+    {
+        . = ALIGN (16);
+        *(.entry.text)
+        *(.init.literal)
+        *(.init)
+    } > iram_seg
+
+    .dram0.bss (NOLOAD) :
+    {
+        . = ALIGN (8);
+        _dram_start = ABSOLUTE(.);
+        _bss_start = ABSOLUTE(.);
+        *(.dynsbss)
+        *(.sbss)
+        *(.sbss.*)
+        *(.gnu.linkonce.sb.*)
+        *(.scommon)
+        *(.sbss2)
+        *(.sbss2.*)
+        *(.gnu.linkonce.sb2.*)
+        *(.dynbss)
+        *(.bss)
+        *(.bss.*)
+        *(.gnu.linkonce.b.*)
+        *(COMMON)
+        . = ALIGN (8);
+        _bss_end = ABSOLUTE(.);
+    } >dram_seg
+
+    .dram0.data :
+    {
+        _data_start = ABSOLUTE(.);
+        *(.data)
+        *(.data.*)
+        *(.gnu.linkonce.d.*)
+        *(.data1)
+        *(.sdata)
+        *(.sdata.*)
+        *(.gnu.linkonce.s.*)
+        *(.sdata2)
+        *(.sdata2.*)
+        *(.gnu.linkonce.s2.*)
+        *(.jcr)
+        _data_end = ABSOLUTE(.);
+    } >dram_seg
+
+    .dram0.rodata :
+    {
+        _rodata_start = ABSOLUTE(.);
+        *(.rodata)
+        *(.rodata.*)
+        *(.gnu.linkonce.r.*)
+        *(.rodata1)
+        __XT_EXCEPTION_TABLE_ = ABSOLUTE(.);
+        *(.xt_except_table)
+        *(.gcc_except_table)
+        *(.gnu.linkonce.e.*)
+        *(.gnu.version_r)
+        *(.eh_frame)
+        . = (. + 3) & ~ 3;
+        /*  C++ constructor and destructor tables, properly ordered:  */
+        __init_array_start = ABSOLUTE(.);
+        KEEP (*crtbegin.*(.ctors))
+        KEEP (*(EXCLUDE_FILE (*crtend.*) .ctors))
+        KEEP (*(SORT(.ctors.*)))
+        KEEP (*(.ctors))
+        __init_array_end = ABSOLUTE(.);
+        KEEP (*crtbegin.*(.dtors))
+        KEEP (*(EXCLUDE_FILE (*crtend.*) .dtors))
+        KEEP (*(SORT(.dtors.*)))
+        KEEP (*(.dtors))
+        /*  C++ exception handlers table:  */
+        __XT_EXCEPTION_DESCS_ = ABSOLUTE(.);
+        *(.xt_except_desc)
+        *(.gnu.linkonce.h.*)
+        __XT_EXCEPTION_DESCS_END__ = ABSOLUTE(.);
+        *(.xt_except_desc_end)
+        *(.dynamic)
+        *(.gnu.version_d)
+        _rodata_end = ABSOLUTE(.);
+        /* Literals are also RO data. */
+        _lit4_start = ABSOLUTE(.);
+        *(*.lit4)
+        *(.lit4.*)
+        *(.gnu.linkonce.lit4.*)
+        _lit4_end = ABSOLUTE(.);
+        . = ALIGN(4);
+        _dram_end = ABSOLUTE(.);
+    } >dram_seg
+
+    .iram.text :
+    {
+        _stext = .;
+        _text_start = ABSOLUTE(.);
+        *(.literal .text .literal.* .text.* .stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
+        *(.iram .iram.*) /* catch stray IRAM_ATTR */
+        *(.fini.literal)
+        *(.fini)
+        *(.gnu.version)
+        _text_end = ABSOLUTE(.);
+        _etext = .;
+    } > iram_seg
+}
diff --git a/boot/espressif/port/esp_mcuboot.c b/boot/espressif/port/esp_mcuboot.c
new file mode 100644
index 0000000..828fc9e
--- /dev/null
+++ b/boot/espressif/port/esp_mcuboot.c
@@ -0,0 +1,216 @@
+/*
+ * Copyright (c) 2021 Espressif Systems (Shanghai) Co., Ltd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <string.h>
+#include <stdlib.h>
+
+#include "mcuboot_config/mcuboot_logging.h"
+#include "flash_map_backend/flash_map_backend.h"
+#include "sysflash/sysflash.h"
+#include "bootutil/bootutil.h"
+
+#define ARRAY_SIZE(arr) sizeof(arr)/sizeof(arr[0])
+
+#define BOOTLOADER_START_ADDRESS 0x1000
+#define BOOTLOADER_SIZE CONFIG_ESP_BOOTLOADER_SIZE
+#define APPLICATION_PRIMARY_START_ADDRESS CONFIG_ESP_APPLICATION_PRIMARY_START_ADDRESS
+#define APPLICATION_SECONDARY_START_ADDRESS CONFIG_ESP_APPLICATION_SECONDARY_START_ADDRESS
+#define APPLICATION_SIZE CONFIG_ESP_APPLICATION_SIZE
+#define SCRATCH_OFFSET CONFIG_ESP_SCRATCH_OFFSET
+#define SCRATCH_SIZE CONFIG_ESP_SCRATCH_SIZE
+
+#define FLASH_SECTOR_SIZE 4096
+
+extern int ets_printf(const char *fmt, ...);
+
+static const struct flash_area bootloader = {
+    .fa_id = FLASH_AREA_BOOTLOADER,
+    .fa_device_id = FLASH_DEVICE_INTERNAL_FLASH,
+    .fa_off = BOOTLOADER_START_ADDRESS,
+    .fa_size = BOOTLOADER_SIZE,
+};
+
+static const struct flash_area primary_img0 = {
+    .fa_id = FLASH_AREA_IMAGE_PRIMARY(0),
+    .fa_device_id = FLASH_DEVICE_INTERNAL_FLASH,
+    .fa_off = APPLICATION_PRIMARY_START_ADDRESS,
+    .fa_size = APPLICATION_SIZE,
+};
+
+static const struct flash_area secondary_img0 = {
+    .fa_id = FLASH_AREA_IMAGE_SECONDARY(0),
+    .fa_device_id = FLASH_DEVICE_INTERNAL_FLASH,
+    .fa_off = APPLICATION_SECONDARY_START_ADDRESS,
+    .fa_size = APPLICATION_SIZE,
+};
+
+static const struct flash_area scratch_img0 = {
+    .fa_id = FLASH_AREA_IMAGE_SCRATCH,
+    .fa_device_id = FLASH_DEVICE_INTERNAL_FLASH,
+    .fa_off = SCRATCH_OFFSET,
+    .fa_size = SCRATCH_SIZE,
+};
+
+static const struct flash_area *s_flash_areas[] = {
+    &bootloader,
+    &primary_img0,
+    &secondary_img0,
+    &scratch_img0,
+};
+
+static const struct flash_area *prv_lookup_flash_area(uint8_t id) {
+    for (size_t i = 0; i < ARRAY_SIZE(s_flash_areas); i++) {
+        const struct flash_area *area = s_flash_areas[i];
+        if (id == area->fa_id) {
+            return area;
+        }
+    }
+    return NULL;
+}
+
+int flash_area_open(uint8_t id, const struct flash_area **area_outp)
+{
+    MCUBOOT_LOG_DBG("%s: ID=%d", __func__, (int)id);
+    const struct flash_area *area = prv_lookup_flash_area(id);
+    *area_outp = area;
+    return area != NULL ? 0 : -1;
+}
+
+void flash_area_close(const struct flash_area *area)
+{
+
+}
+
+int flash_area_read(const struct flash_area *fa, uint32_t off, void *dst,
+                    uint32_t len)
+{
+    if (fa->fa_device_id != FLASH_DEVICE_INTERNAL_FLASH) {
+        return -1;
+    }
+
+    const uint32_t end_offset = off + len;
+    if (end_offset > fa->fa_size) {
+        MCUBOOT_LOG_ERR("%s: Out of Bounds (0x%x vs 0x%x)", __func__, end_offset, fa->fa_size);
+        return -1;
+    }
+
+    return 0;
+}
+
+int flash_area_write(const struct flash_area *fa, uint32_t off, const void *src,
+                     uint32_t len)
+{
+    if (fa->fa_device_id != FLASH_DEVICE_INTERNAL_FLASH) {
+        return -1;
+    }
+
+    const uint32_t end_offset = off + len;
+    if (end_offset > fa->fa_size) {
+        MCUBOOT_LOG_ERR("%s: Out of Bounds (0x%x vs 0x%x)", __func__, end_offset, fa->fa_size);
+        return -1;
+    }
+
+    const uint32_t addr = fa->fa_off + off;
+    MCUBOOT_LOG_DBG("%s: Addr: 0x%08x Length: %d", __func__, (int)addr, (int)len);
+
+#if VALIDATE_PROGRAM_OP
+    if (memcmp((void *)addr, src, len) != 0) {
+        MCUBOOT_LOG_ERR("%s: Program Failed", __func__);
+        assert(0);
+    }
+#endif
+
+    return 0;
+}
+
+int flash_area_erase(const struct flash_area *fa, uint32_t off, uint32_t len)
+{
+    if (fa->fa_device_id != FLASH_DEVICE_INTERNAL_FLASH) {
+        return -1;
+    }
+
+    if ((len % FLASH_SECTOR_SIZE) != 0 || (off % FLASH_SECTOR_SIZE) != 0) {
+        MCUBOOT_LOG_ERR("%s: Not aligned on sector Offset: 0x%x Length: 0x%x", __func__,
+                    (int)off, (int)len);
+        return -1;
+    }
+
+    const uint32_t start_addr = fa->fa_off + off;
+    MCUBOOT_LOG_DBG("%s: Addr: 0x%08x Length: %d", __func__, (int)start_addr, (int)len);
+
+#if VALIDATE_PROGRAM_OP
+    for (size_t i = 0; i < len; i++) {
+        uint8_t *val = (void *)(start_addr + i);
+        if (*val != 0xff) {
+            MCUBOOT_LOG_ERR("%s: Erase at 0x%x Failed", __func__, (int)val);
+            assert(0);
+        }
+    }
+#endif
+
+    return 0;
+}
+
+size_t flash_area_align(const struct flash_area *area)
+{
+    return 4;
+}
+
+uint8_t flash_area_erased_val(const struct flash_area *area)
+{
+    return 0xff;
+}
+
+int flash_area_get_sectors(int fa_id, uint32_t *count,
+                           struct flash_sector *sectors)
+{
+    const struct flash_area *fa = prv_lookup_flash_area(fa_id);
+    if (fa->fa_device_id != FLASH_DEVICE_INTERNAL_FLASH) {
+        return -1;
+    }
+
+    const size_t sector_size = FLASH_SECTOR_SIZE;
+    uint32_t total_count = 0;
+    for (size_t off = 0; off < fa->fa_size; off += sector_size) {
+        // Note: Offset here is relative to flash area, not device
+        sectors[total_count].fs_off = off;
+        sectors[total_count].fs_size = sector_size;
+        total_count++;
+    }
+
+    *count = total_count;
+    return 0;
+}
+
+int flash_area_id_from_multi_image_slot(int image_index, int slot)
+{
+    MCUBOOT_LOG_DBG("%s", __func__);
+    switch (slot) {
+      case 0:
+        return FLASH_AREA_IMAGE_PRIMARY(image_index);
+      case 1:
+        return FLASH_AREA_IMAGE_SECONDARY(image_index);
+    }
+
+    MCUBOOT_LOG_ERR("Unexpected Request: image_index=%d, slot=%d", image_index, slot);
+    return -1; /* flash_area_open will fail on that */
+}
+
+int flash_area_id_from_image_slot(int slot)
+{
+  return flash_area_id_from_multi_image_slot(0, slot);
+}
+
+int flash_area_to_sectors(int idx, int *cnt, struct flash_area *fa)
+{
+	return -1;
+}
+
+void mcuboot_assert_handler(const char *file, int line, const char *func)
+{
+    ets_printf("assertion failed: file \"%s\", line %d, func: %s\n", file, line, func);
+    abort();
+}