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1/* ESP32 Linker Script Memory Layout
2
3   This file describes the memory layout (memory blocks) as virtual
4   memory addresses.
5
6   esp32.project.ld contains output sections to link compiler output
7   into these memory blocks.
8
9   ***
10
11   This linker script is passed through the C preprocessor to include
12   configuration options.
13
14   Please use preprocessor features sparingly! Restrict
15   to simple macros with numeric values, and/or #if/#endif blocks.
16*/
17#include "sdkconfig.h"
18
19/* If BT is not built at all */
20#ifndef CONFIG_BT_RESERVE_DRAM
21#define CONFIG_BT_RESERVE_DRAM 0
22#endif
23
24#ifdef CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC
25#define ESP_BOOTLOADER_RESERVE_RTC (CONFIG_BOOTLOADER_RESERVE_RTC_SIZE + CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC_SIZE)
26#elif defined(CONFIG_BOOTLOADER_SKIP_VALIDATE_IN_DEEP_SLEEP)
27#define ESP_BOOTLOADER_RESERVE_RTC (CONFIG_BOOTLOADER_RESERVE_RTC_SIZE)
28#else
29#define ESP_BOOTLOADER_RESERVE_RTC 0
30#endif
31
32#if defined(CONFIG_ESP32_USE_FIXED_STATIC_RAM_SIZE)
33
34ASSERT((CONFIG_ESP32_FIXED_STATIC_RAM_SIZE <= 0x2c200),
35          "Fixed static ram data does not fit.")
36
37#define DRAM0_0_SEG_LEN CONFIG_ESP32_FIXED_STATIC_RAM_SIZE
38
39#else
40#define DRAM0_0_SEG_LEN 0x2c200
41#endif
42
43MEMORY
44{
45  /* All these values assume the flash cache is on, and have the blocks this uses subtracted from the length
46  of the various regions. The 'data access port' dram/drom regions map to the same iram/irom regions but
47  are connected to the data port of the CPU and eg allow bytewise access. */
48
49  /* IRAM for PRO cpu. Not sure if happy with this, this is MMU area... */
50  iram0_0_seg (RX) :                 org = 0x40080000, len = 0x20000
51
52#ifdef CONFIG_APP_BUILD_USE_FLASH_SECTIONS
53  /* Even though the segment name is iram, it is actually mapped to flash
54  */
55  iram0_2_seg (RX) :                 org = 0x400D0020, len = 0x330000-0x20
56
57  /*
58    (0x20 offset above is a convenience for the app binary image generation.
59    Flash cache has 64KB pages. The .bin file which is flashed to the chip
60    has a 0x18 byte file header, and each segment has a 0x08 byte segment
61    header. Setting this offset makes it simple to meet the flash cache MMU's
62    constraint that (paddr % 64KB == vaddr % 64KB).)
63  */
64#endif // CONFIG_APP_BUILD_USE_FLASH_SECTIONS
65
66
67  /* Shared data RAM, excluding memory reserved for ROM bss/data/stack.
68
69     Enabling Bluetooth & Trace Memory features in menuconfig will decrease
70     the amount of RAM available.
71
72     Note: Length of this section *should* be 0x50000, and this extra DRAM is available
73     in heap at runtime. However due to static ROM memory usage at this 176KB mark, the
74     additional static memory temporarily cannot be used.
75  */
76  dram0_0_seg (RW) :                 org = 0x3FFB0000 + CONFIG_BT_RESERVE_DRAM,
77                                     len = DRAM0_0_SEG_LEN - CONFIG_BT_RESERVE_DRAM
78
79#ifdef CONFIG_APP_BUILD_USE_FLASH_SECTIONS
80  /* Flash mapped constant data */
81  drom0_0_seg (R) :                  org = 0x3F400020, len = 0x400000-0x20
82
83  /* (See iram0_2_seg for meaning of 0x20 offset in the above.) */
84#endif // CONFIG_APP_BUILD_USE_FLASH_SECTIONS
85
86  /* RTC fast memory (executable). Persists over deep sleep.
87   */
88  rtc_iram_seg(RWX) :                org = 0x400C0000, len = 0x2000
89
90  /* RTC fast memory (same block as above), viewed from data bus */
91  rtc_data_seg(RW) :                 org = 0x3ff80000, len = 0x2000 - ESP_BOOTLOADER_RESERVE_RTC
92
93  /* RTC slow memory (data accessible). Persists over deep sleep.
94
95     Start of RTC slow memory is reserved for ULP co-processor code + data, if enabled.
96  */
97  rtc_slow_seg(RW)  :                org = 0x50000000 + CONFIG_ESP32_ULP_COPROC_RESERVE_MEM,
98                                     len = 0x2000 - CONFIG_ESP32_ULP_COPROC_RESERVE_MEM
99
100  /* external memory ,including data and text */
101  extern_ram_seg(RWX)  :             org = 0x3F800000,
102                                     len = 0x400000
103}
104
105#if defined(CONFIG_ESP32_USE_FIXED_STATIC_RAM_SIZE)
106/* static data ends at defined address */
107_static_data_end = 0x3FFB0000 + DRAM0_0_SEG_LEN;
108#else
109_static_data_end = _bss_end;
110#endif
111
112/* Heap ends at top of dram0_0_seg */
113_heap_end = 0x40000000 - CONFIG_ESP32_TRACEMEM_RESERVE_DRAM;
114
115_data_seg_org = ORIGIN(rtc_data_seg);
116
117/* The lines below define location alias for .rtc.data section based on Kconfig option.
118   When the option is not defined then use slow memory segment
119   else the data will be placed in fast memory segment */
120#ifndef CONFIG_ESP32_RTCDATA_IN_FAST_MEM
121REGION_ALIAS("rtc_data_location", rtc_slow_seg );
122#else
123REGION_ALIAS("rtc_data_location", rtc_data_seg );
124#endif
125
126#ifdef CONFIG_APP_BUILD_USE_FLASH_SECTIONS
127  REGION_ALIAS("default_code_seg", iram0_2_seg);
128#else
129  REGION_ALIAS("default_code_seg", iram0_0_seg);
130#endif // CONFIG_APP_BUILD_USE_FLASH_SECTIONS
131
132#ifdef CONFIG_APP_BUILD_USE_FLASH_SECTIONS
133  REGION_ALIAS("default_rodata_seg", drom0_0_seg);
134#else
135  REGION_ALIAS("default_rodata_seg", dram0_0_seg);
136#endif // CONFIG_APP_BUILD_USE_FLASH_SECTIONS
137
138/**
139 *  If rodata default segment is placed in `drom0_0_seg`, then flash's first rodata section must
140 *  also be first in the segment.
141 */
142#ifdef CONFIG_APP_BUILD_USE_FLASH_SECTIONS
143  ASSERT(_rodata_start == ORIGIN(default_rodata_seg),
144         ".flash.appdesc section must be placed at the beginning of the rodata segment.")
145#endif
146