spiram.c 15 KB

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  1. /*
  2. Abstraction layer for spi-ram. For now, it's no more than a stub for the spiram_psram functions, but if
  3. we add more types of external RAM memory, this can be made into a more intelligent dispatcher.
  4. */
  5. // Copyright 2015-2017 Espressif Systems (Shanghai) PTE LTD
  6. //
  7. // Licensed under the Apache License, Version 2.0 (the "License");
  8. // you may not use this file except in compliance with the License.
  9. // You may obtain a copy of the License at
  10. //
  11. // http://www.apache.org/licenses/LICENSE-2.0
  12. //
  13. // Unless required by applicable law or agreed to in writing, software
  14. // distributed under the License is distributed on an "AS IS" BASIS,
  15. // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16. // See the License for the specific language governing permissions and
  17. // limitations under the License.
  18. #include <stdint.h>
  19. #include <string.h>
  20. #include <sys/param.h>
  21. #include "sdkconfig.h"
  22. #include "esp_attr.h"
  23. #include "esp_err.h"
  24. #include "esp32s2/spiram.h"
  25. #include "spiram_psram.h"
  26. #include "esp_log.h"
  27. #include "freertos/FreeRTOS.h"
  28. #include "freertos/xtensa_api.h"
  29. #include "soc/soc.h"
  30. #include "esp_heap_caps_init.h"
  31. #include "soc/soc_memory_layout.h"
  32. #include "soc/dport_reg.h"
  33. #include "esp32s2/rom/cache.h"
  34. #include "soc/cache_memory.h"
  35. #include "soc/extmem_reg.h"
  36. #define PSRAM_MODE PSRAM_VADDR_MODE_NORMAL
  37. #if CONFIG_SPIRAM
  38. static const char* TAG = "spiram";
  39. #if CONFIG_SPIRAM_SPEED_40M
  40. #define PSRAM_SPEED PSRAM_CACHE_S40M
  41. #elif CONFIG_SPIRAM_SPEED_80M
  42. #define PSRAM_SPEED PSRAM_CACHE_S80M
  43. #else
  44. #define PSRAM_SPEED PSRAM_CACHE_S20M
  45. #endif
  46. static bool spiram_inited=false;
  47. /*
  48. Simple RAM test. Writes a word every 32 bytes. Takes about a second to complete for 4MiB. Returns
  49. true when RAM seems OK, false when test fails. WARNING: Do not run this before the 2nd cpu has been
  50. initialized (in a two-core system) or after the heap allocator has taken ownership of the memory.
  51. */
  52. bool esp_spiram_test(void)
  53. {
  54. size_t spiram_size = esp_spiram_get_size();
  55. volatile int *spiram=(volatile int*)(SOC_EXTRAM_DATA_HIGH - spiram_size);
  56. size_t p;
  57. size_t s = spiram_size;
  58. int errct=0;
  59. int initial_err=-1;
  60. if (SOC_EXTRAM_DATA_SIZE < spiram_size) {
  61. ESP_EARLY_LOGW(TAG, "Only test spiram from %08x to %08x\n", SOC_EXTRAM_DATA_LOW, SOC_EXTRAM_DATA_HIGH);
  62. spiram=(volatile int*)SOC_EXTRAM_DATA_LOW;
  63. s = SOC_EXTRAM_DATA_SIZE;
  64. }
  65. for (p=0; p<(s/sizeof(int)); p+=8) {
  66. spiram[p]=p^0xAAAAAAAA;
  67. }
  68. for (p=0; p<(s/sizeof(int)); p+=8) {
  69. if (spiram[p]!=(p^0xAAAAAAAA)) {
  70. errct++;
  71. if (errct==1) initial_err=p*4;
  72. if (errct < 4) {
  73. ESP_EARLY_LOGE(TAG, "SPI SRAM error@%08x:%08x/%08x \n", &spiram[p], spiram[p], p^0xAAAAAAAA);
  74. }
  75. }
  76. }
  77. if (errct) {
  78. ESP_EARLY_LOGE(TAG, "SPI SRAM memory test fail. %d/%d writes failed, first @ %X\n", errct, s/32, initial_err+SOC_EXTRAM_DATA_LOW);
  79. return false;
  80. } else {
  81. ESP_EARLY_LOGI(TAG, "SPI SRAM memory test OK");
  82. return true;
  83. }
  84. }
  85. #define DRAM0_ONLY_CACHE_SIZE BUS_IRAM0_CACHE_SIZE
  86. #define DRAM0_DRAM1_CACHE_SIZE (BUS_IRAM0_CACHE_SIZE + BUS_IRAM1_CACHE_SIZE)
  87. #define DRAM0_DRAM1_DPORT_CACHE_SIZE (BUS_IRAM0_CACHE_SIZE + BUS_IRAM1_CACHE_SIZE + BUS_DPORT_CACHE_SIZE)
  88. #define DBUS3_ONLY_CACHE_SIZE BUS_AHB_DBUS3_CACHE_SIZE
  89. #define DRAM0_DRAM1_DPORT_DBUS3_CACHE_SIZE (DRAM0_DRAM1_DPORT_CACHE_SIZE + DBUS3_ONLY_CACHE_SIZE)
  90. #define SPIRAM_SIZE_EXC_DRAM0_DRAM1_DPORT (spiram_size - DRAM0_DRAM1_DPORT_CACHE_SIZE)
  91. #define SPIRAM_SIZE_EXC_DATA_CACHE (spiram_size - DRAM0_DRAM1_DPORT_DBUS3_CACHE_SIZE)
  92. #define SPIRAM_SMALL_SIZE_MAP_VADDR (DRAM0_CACHE_ADDRESS_HIGH - spiram_size)
  93. #define SPIRAM_SMALL_SIZE_MAP_PADDR 0
  94. #define SPIRAM_SMALL_SIZE_MAP_SIZE spiram_size
  95. #define SPIRAM_MID_SIZE_MAP_VADDR (AHB_DBUS3_ADDRESS_HIGH - SPIRAM_SIZE_EXC_DRAM0_DRAM1_DPORT)
  96. #define SPIRAM_MID_SIZE_MAP_PADDR 0
  97. #define SPIRAM_MID_SIZE_MAP_SIZE (SPIRAM_SIZE_EXC_DRAM0_DRAM1_DPORT)
  98. #define SPIRAM_BIG_SIZE_MAP_VADDR AHB_DBUS3_ADDRESS_LOW
  99. #define SPIRAM_BIG_SIZE_MAP_PADDR (AHB_DBUS3_ADDRESS_HIGH - DRAM0_DRAM1_DPORT_DBUS3_CACHE_SIZE)
  100. #define SPIRAM_BIG_SIZE_MAP_SIZE DBUS3_ONLY_CACHE_SIZE
  101. #define SPIRAM_MID_BIG_SIZE_MAP_VADDR DPORT_CACHE_ADDRESS_LOW
  102. #define SPIRAM_MID_BIG_SIZE_MAP_PADDR SPIRAM_SIZE_EXC_DRAM0_DRAM1_DPORT
  103. #define SPIRAM_MID_BIG_SIZE_MAP_SIZE DRAM0_DRAM1_DPORT_DBUS3_CACHE_SIZE
  104. void IRAM_ATTR esp_spiram_init_cache(void)
  105. {
  106. size_t spiram_size = esp_spiram_get_size();
  107. Cache_Suspend_DCache();
  108. /* map the address from SPIRAM end to the start, map the address in order: DRAM1, DRAM1, DPORT, DBUS3 */
  109. if (spiram_size <= DRAM0_ONLY_CACHE_SIZE) {
  110. /* cache size <= 3MB + 512 KB, only map DRAM0 bus */
  111. Cache_Dbus_MMU_Set(MMU_ACCESS_SPIRAM, SPIRAM_SMALL_SIZE_MAP_VADDR, SPIRAM_SMALL_SIZE_MAP_PADDR, 64, SPIRAM_SMALL_SIZE_MAP_SIZE >> 16, 0);
  112. REG_CLR_BIT(EXTMEM_PRO_DCACHE_CTRL1_REG, EXTMEM_PRO_DCACHE_MASK_DRAM0);
  113. } else if (spiram_size <= DRAM0_DRAM1_CACHE_SIZE) {
  114. /* cache size <= 7MB + 512KB, only map DRAM0 and DRAM1 bus */
  115. Cache_Dbus_MMU_Set(MMU_ACCESS_SPIRAM, SPIRAM_SMALL_SIZE_MAP_VADDR, SPIRAM_SMALL_SIZE_MAP_PADDR, 64, SPIRAM_SMALL_SIZE_MAP_SIZE >> 16, 0);
  116. REG_CLR_BIT(EXTMEM_PRO_DCACHE_CTRL1_REG, EXTMEM_PRO_DCACHE_MASK_DRAM1 | EXTMEM_PRO_DCACHE_MASK_DRAM0);
  117. } else if (spiram_size <= DRAM0_DRAM1_DPORT_CACHE_SIZE) {
  118. /* cache size <= 10MB + 512KB, map DRAM0, DRAM1, DPORT bus */
  119. Cache_Dbus_MMU_Set(MMU_ACCESS_SPIRAM, SPIRAM_SMALL_SIZE_MAP_VADDR, SPIRAM_SMALL_SIZE_MAP_PADDR, 64, SPIRAM_SMALL_SIZE_MAP_SIZE >> 16, 0);
  120. REG_CLR_BIT(EXTMEM_PRO_DCACHE_CTRL1_REG, EXTMEM_PRO_DCACHE_MASK_DRAM1 | EXTMEM_PRO_DCACHE_MASK_DRAM0 | EXTMEM_PRO_DCACHE_MASK_DPORT);
  121. } else {
  122. /* cache size > 10MB + 512KB, map DRAM0, DRAM1, DPORT bus , only remap 0x3f500000 ~ 0x3ff90000*/
  123. Cache_Dbus_MMU_Set(MMU_ACCESS_SPIRAM, DPORT_CACHE_ADDRESS_LOW, SPIRAM_SMALL_SIZE_MAP_PADDR, 64, DRAM0_DRAM1_DPORT_CACHE_SIZE >> 16, 0);
  124. REG_CLR_BIT(EXTMEM_PRO_DCACHE_CTRL1_REG, EXTMEM_PRO_DCACHE_MASK_DRAM1 | EXTMEM_PRO_DCACHE_MASK_DRAM0 | EXTMEM_PRO_DCACHE_MASK_DPORT);
  125. }
  126. Cache_Resume_DCache(0);
  127. }
  128. static uint32_t pages_for_flash = 0;
  129. static uint32_t instrcution_in_spiram = 0;
  130. static uint32_t rodata_in_spiram = 0;
  131. #if CONFIG_SPIRAM_FETCH_INSTRUCTIONS
  132. static int instr_flash2spiram_offs = 0;
  133. static uint32_t instr_start_page = 0;
  134. static uint32_t instr_end_page = 0;
  135. #endif
  136. #if CONFIG_SPIRAM_RODATA
  137. static int rodata_flash2spiram_offs = 0;
  138. static uint32_t rodata_start_page = 0;
  139. static uint32_t rodata_end_page = 0;
  140. #endif
  141. #if CONFIG_SPIRAM_FETCH_INSTRUCTIONS || CONFIG_SPIRAM_RODATA
  142. static uint32_t page0_mapped = 0;
  143. static uint32_t page0_page = INVALID_PHY_PAGE;
  144. #endif
  145. uint32_t esp_spiram_instruction_access_enabled(void)
  146. {
  147. return instrcution_in_spiram;
  148. }
  149. uint32_t esp_spiram_rodata_access_enabled(void)
  150. {
  151. return rodata_in_spiram;
  152. }
  153. #if CONFIG_SPIRAM_FETCH_INSTRUCTIONS
  154. esp_err_t esp_spiram_enable_instruction_access(void)
  155. {
  156. size_t spiram_size = esp_spiram_get_size();
  157. uint32_t pages_in_flash = 0;
  158. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_IBUS0, &page0_mapped);
  159. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_IBUS1, &page0_mapped);
  160. if ((pages_in_flash + pages_for_flash) > (spiram_size >> 16)) {
  161. ESP_EARLY_LOGE(TAG, "SPI RAM space not enough for the instructions, has %d pages, need %d pages.", (spiram_size >> 16), (pages_in_flash + pages_for_flash));
  162. return ESP_FAIL;
  163. }
  164. ESP_EARLY_LOGI(TAG, "Instructions copied and mapped to SPIRAM");
  165. uint32_t instr_mmu_offset = ((uint32_t)&_instruction_reserved_start & 0xFFFFFF)/MMU_PAGE_SIZE;
  166. uint32_t mmu_value = *(volatile uint32_t *)(DR_REG_MMU_TABLE + PRO_CACHE_IBUS0_MMU_START + instr_mmu_offset*sizeof(uint32_t));
  167. mmu_value &= MMU_ADDRESS_MASK;
  168. instr_flash2spiram_offs = mmu_value - pages_for_flash;
  169. ESP_EARLY_LOGV(TAG, "Instructions from flash page%d copy to SPIRAM page%d, Offset: %d", mmu_value, pages_for_flash, instr_flash2spiram_offs);
  170. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_IBUS0, IRAM0_ADDRESS_LOW, pages_for_flash, &page0_page);
  171. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_IBUS1, IRAM1_ADDRESS_LOW, pages_for_flash, &page0_page);
  172. instrcution_in_spiram = 1;
  173. return ESP_OK;
  174. }
  175. #endif
  176. #if CONFIG_SPIRAM_RODATA
  177. esp_err_t esp_spiram_enable_rodata_access(void)
  178. {
  179. uint32_t pages_in_flash = 0;
  180. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_IBUS2, &page0_mapped);
  181. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_DBUS0, &page0_mapped);
  182. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_DBUS1, &page0_mapped);
  183. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_DBUS2, &page0_mapped);
  184. if ((pages_in_flash + pages_for_flash) > (esp_spiram_get_size() >> 16)) {
  185. ESP_EARLY_LOGE(TAG, "SPI RAM space not enough for the read only data.");
  186. return ESP_FAIL;
  187. }
  188. ESP_EARLY_LOGI(TAG, "Read only data copied and mapped to SPIRAM");
  189. uint32_t rodata_mmu_offset = ((uint32_t)&_rodata_reserved_start & 0xFFFFFF)/MMU_PAGE_SIZE;
  190. uint32_t mmu_value = *(volatile uint32_t *)(DR_REG_MMU_TABLE + PRO_CACHE_IBUS2_MMU_START + rodata_mmu_offset*sizeof(uint32_t));
  191. mmu_value &= MMU_ADDRESS_MASK;
  192. rodata_flash2spiram_offs = mmu_value - pages_for_flash;
  193. ESP_EARLY_LOGV(TAG, "Rodata from flash page%d copy to SPIRAM page%d, Offset: %d", mmu_value, pages_for_flash, rodata_flash2spiram_offs);
  194. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_IBUS2, DROM0_ADDRESS_LOW, pages_for_flash, &page0_page);
  195. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_DBUS0, DRAM0_ADDRESS_LOW, pages_for_flash, &page0_page);
  196. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_DBUS1, DRAM1_ADDRESS_LOW, pages_for_flash, &page0_page);
  197. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_DBUS2, DPORT_ADDRESS_LOW, pages_for_flash, &page0_page);
  198. rodata_in_spiram = 1;
  199. return ESP_OK;
  200. }
  201. #endif
  202. #if CONFIG_SPIRAM_FETCH_INSTRUCTIONS
  203. void instruction_flash_page_info_init(void)
  204. {
  205. uint32_t instr_page_cnt = ((uint32_t)&_instruction_reserved_end - SOC_IROM_LOW + MMU_PAGE_SIZE - 1)/MMU_PAGE_SIZE;
  206. uint32_t instr_mmu_offset = ((uint32_t)&_instruction_reserved_start & 0xFFFFFF)/MMU_PAGE_SIZE;
  207. instr_start_page = *(volatile uint32_t *)(DR_REG_MMU_TABLE + PRO_CACHE_IBUS0_MMU_START + instr_mmu_offset*sizeof(uint32_t));
  208. instr_start_page &= MMU_ADDRESS_MASK;
  209. instr_end_page = instr_start_page + instr_page_cnt - 1;
  210. }
  211. uint32_t IRAM_ATTR instruction_flash_start_page_get(void)
  212. {
  213. return instr_start_page;
  214. }
  215. uint32_t IRAM_ATTR instruction_flash_end_page_get(void)
  216. {
  217. return instr_end_page;
  218. }
  219. int IRAM_ATTR instruction_flash2spiram_offset(void)
  220. {
  221. return instr_flash2spiram_offs;
  222. }
  223. #endif
  224. #if CONFIG_SPIRAM_RODATA
  225. void rodata_flash_page_info_init(void)
  226. {
  227. uint32_t rodata_page_cnt = ((uint32_t)&_rodata_reserved_end - SOC_DROM_LOW + MMU_PAGE_SIZE - 1)/MMU_PAGE_SIZE;
  228. uint32_t rodata_mmu_offset = ((uint32_t)&_rodata_reserved_start & 0xFFFFFF)/MMU_PAGE_SIZE;
  229. rodata_start_page = *(volatile uint32_t *)(DR_REG_MMU_TABLE + PRO_CACHE_IBUS2_MMU_START + rodata_mmu_offset*sizeof(uint32_t));
  230. rodata_start_page &= MMU_ADDRESS_MASK;
  231. rodata_end_page = rodata_start_page + rodata_page_cnt - 1;
  232. }
  233. uint32_t IRAM_ATTR rodata_flash_start_page_get(void)
  234. {
  235. return rodata_start_page;
  236. }
  237. uint32_t IRAM_ATTR rodata_flash_end_page_get(void)
  238. {
  239. return rodata_end_page;
  240. }
  241. int IRAM_ATTR rodata_flash2spiram_offset(void)
  242. {
  243. return rodata_flash2spiram_offs;
  244. }
  245. #endif
  246. esp_err_t esp_spiram_init(void)
  247. {
  248. esp_err_t r;
  249. r = psram_enable(PSRAM_SPEED, PSRAM_MODE);
  250. if (r != ESP_OK) {
  251. #if CONFIG_SPIRAM_IGNORE_NOTFOUND
  252. ESP_EARLY_LOGE(TAG, "SPI RAM enabled but initialization failed. Bailing out.");
  253. #endif
  254. return r;
  255. }
  256. spiram_inited = true;
  257. size_t spiram_size = esp_spiram_get_size();
  258. #if (CONFIG_SPIRAM_SIZE != -1)
  259. if (spiram_size != CONFIG_SPIRAM_SIZE) {
  260. ESP_EARLY_LOGE(TAG, "Expected %dKiB chip but found %dKiB chip. Bailing out..", CONFIG_SPIRAM_SIZE/1024, spiram_size/1024);
  261. return ESP_ERR_INVALID_SIZE;
  262. }
  263. #endif
  264. ESP_EARLY_LOGI(TAG, "Found %dMBit SPI RAM device",
  265. (spiram_size*8)/(1024*1024));
  266. ESP_EARLY_LOGI(TAG, "SPI RAM mode: %s", PSRAM_SPEED == PSRAM_CACHE_S40M ? "sram 40m" : \
  267. PSRAM_SPEED == PSRAM_CACHE_S80M ? "sram 80m" : "sram 20m");
  268. ESP_EARLY_LOGI(TAG, "PSRAM initialized, cache is in %s mode.", \
  269. (PSRAM_MODE==PSRAM_VADDR_MODE_EVENODD)?"even/odd (2-core)": \
  270. (PSRAM_MODE==PSRAM_VADDR_MODE_LOWHIGH)?"low/high (2-core)": \
  271. (PSRAM_MODE==PSRAM_VADDR_MODE_NORMAL)?"normal (1-core)":"ERROR");
  272. return ESP_OK;
  273. }
  274. esp_err_t esp_spiram_add_to_heapalloc(void)
  275. {
  276. size_t spiram_size = esp_spiram_get_size();
  277. uint32_t size_for_flash = (pages_for_flash << 16);
  278. intptr_t vaddr;
  279. ESP_EARLY_LOGI(TAG, "Adding pool of %dK of external SPI memory to heap allocator", (spiram_size - (pages_for_flash << 16))/1024);
  280. //Add entire external RAM region to heap allocator. Heap allocator knows the capabilities of this type of memory, so there's
  281. //no need to explicitly specify them.
  282. if (spiram_size <= DRAM0_DRAM1_DPORT_CACHE_SIZE) {
  283. /* cache size <= 10MB + 512KB, map DRAM0, DRAM1, DPORT bus */
  284. vaddr = SPIRAM_SMALL_SIZE_MAP_VADDR;
  285. return heap_caps_add_region(vaddr + size_for_flash, vaddr + spiram_size - 1);
  286. }
  287. vaddr = DPORT_CACHE_ADDRESS_LOW;
  288. Cache_Dbus_MMU_Set(MMU_ACCESS_SPIRAM, vaddr, SPIRAM_SMALL_SIZE_MAP_PADDR, 64, DRAM0_DRAM1_DPORT_CACHE_SIZE >> 16, 0);
  289. if (size_for_flash <= SPIRAM_SIZE_EXC_DRAM0_DRAM1_DPORT) {
  290. return heap_caps_add_region(vaddr, vaddr + DRAM0_DRAM1_DPORT_CACHE_SIZE - 1);
  291. }
  292. // Largest size
  293. return heap_caps_add_region(vaddr + size_for_flash, vaddr + DRAM0_DRAM1_DPORT_CACHE_SIZE -1);
  294. }
  295. static uint8_t *dma_heap;
  296. esp_err_t esp_spiram_reserve_dma_pool(size_t size) {
  297. if (size==0) return ESP_OK; //no-op
  298. ESP_EARLY_LOGI(TAG, "Reserving pool of %dK of internal memory for DMA/internal allocations", size/1024);
  299. dma_heap=heap_caps_malloc(size, MALLOC_CAP_DMA|MALLOC_CAP_INTERNAL);
  300. if (!dma_heap) return ESP_ERR_NO_MEM;
  301. uint32_t caps[]={MALLOC_CAP_DMA|MALLOC_CAP_INTERNAL, 0, MALLOC_CAP_8BIT|MALLOC_CAP_32BIT};
  302. return heap_caps_add_region_with_caps(caps, (intptr_t) dma_heap, (intptr_t) dma_heap+size-1);
  303. }
  304. size_t esp_spiram_get_size(void)
  305. {
  306. if (!spiram_inited) {
  307. ESP_EARLY_LOGE(TAG, "SPI RAM not initialized");
  308. abort();
  309. }
  310. psram_size_t size=psram_get_size();
  311. if (size==PSRAM_SIZE_16MBITS) return 2*1024*1024;
  312. if (size==PSRAM_SIZE_32MBITS) return 4*1024*1024;
  313. if (size==PSRAM_SIZE_64MBITS) return 8*1024*1024;
  314. return CONFIG_SPIRAM_SIZE;
  315. }
  316. /*
  317. Before flushing the cache, if psram is enabled as a memory-mapped thing, we need to write back the data in the cache to the psram first,
  318. otherwise it will get lost. For now, we just read 64/128K of random PSRAM memory to do this.
  319. */
  320. void IRAM_ATTR esp_spiram_writeback_cache(void)
  321. {
  322. extern void Cache_WriteBack_All(void);
  323. Cache_WriteBack_All();
  324. }
  325. #endif