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. #define SPIRAM_SIZE esp_spiram_get_size()
  47. static bool spiram_inited=false;
  48. /*
  49. Simple RAM test. Writes a word every 32 bytes. Takes about a second to complete for 4MiB. Returns
  50. true when RAM seems OK, false when test fails. WARNING: Do not run this before the 2nd cpu has been
  51. initialized (in a two-core system) or after the heap allocator has taken ownership of the memory.
  52. */
  53. bool esp_spiram_test(void)
  54. {
  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_HIGH - SOC_EXTRAM_DATA_LOW) < 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_HIGH - SOC_EXTRAM_DATA_LOW;
  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. Cache_Suspend_DCache();
  107. /* map the address from SPIRAM end to the start, map the address in order: DRAM1, DRAM1, DPORT, DBUS3 */
  108. if (SPIRAM_SIZE <= DRAM0_ONLY_CACHE_SIZE) {
  109. /* cache size <= 3MB + 512 KB, only map DRAM0 bus */
  110. 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);
  111. REG_CLR_BIT(EXTMEM_PRO_DCACHE_CTRL1_REG, EXTMEM_PRO_DCACHE_MASK_DRAM0);
  112. } else if (SPIRAM_SIZE <= DRAM0_DRAM1_CACHE_SIZE) {
  113. /* cache size <= 7MB + 512KB, only map DRAM0 and DRAM1 bus */
  114. 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);
  115. REG_CLR_BIT(EXTMEM_PRO_DCACHE_CTRL1_REG, EXTMEM_PRO_DCACHE_MASK_DRAM1 | EXTMEM_PRO_DCACHE_MASK_DRAM0);
  116. } else if (SPIRAM_SIZE <= DRAM0_DRAM1_DPORT_CACHE_SIZE) {
  117. /* cache size <= 10MB + 512KB, map DRAM0, DRAM1, DPORT bus */
  118. 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);
  119. REG_CLR_BIT(EXTMEM_PRO_DCACHE_CTRL1_REG, EXTMEM_PRO_DCACHE_MASK_DRAM1 | EXTMEM_PRO_DCACHE_MASK_DRAM0 | EXTMEM_PRO_DCACHE_MASK_DPORT);
  120. } else {
  121. /* cache size > 10MB + 512KB, map DRAM0, DRAM1, DPORT bus , only remap 0x3f500000 ~ 0x3ff90000*/
  122. Cache_Dbus_MMU_Set(MMU_ACCESS_SPIRAM, DPORT_CACHE_ADDRESS_LOW, SPIRAM_SMALL_SIZE_MAP_PADDR, 64, DRAM0_DRAM1_DPORT_CACHE_SIZE >> 16, 0);
  123. REG_CLR_BIT(EXTMEM_PRO_DCACHE_CTRL1_REG, EXTMEM_PRO_DCACHE_MASK_DRAM1 | EXTMEM_PRO_DCACHE_MASK_DRAM0 | EXTMEM_PRO_DCACHE_MASK_DPORT);
  124. }
  125. Cache_Resume_DCache(0);
  126. }
  127. static uint32_t pages_for_flash = 0;
  128. static uint32_t page0_mapped = 0;
  129. static uint32_t page0_page = INVALID_PHY_PAGE;
  130. static uint32_t instrcution_in_spiram = 0;
  131. static uint32_t rodata_in_spiram = 0;
  132. #if CONFIG_SPIRAM_FETCH_INSTRUCTIONS
  133. static int instr_flash2spiram_offs = 0;
  134. static uint32_t instr_start_page = 0;
  135. static uint32_t instr_end_page = 0;
  136. #endif
  137. #if CONFIG_SPIRAM_RODATA
  138. static int rodata_flash2spiram_offs = 0;
  139. static uint32_t rodata_start_page = 0;
  140. static uint32_t rodata_end_page = 0;
  141. #endif
  142. uint32_t esp_spiram_instruction_access_enabled(void)
  143. {
  144. return instrcution_in_spiram;
  145. }
  146. uint32_t esp_spiram_rodata_access_enabled(void)
  147. {
  148. return rodata_in_spiram;
  149. }
  150. #if CONFIG_SPIRAM_FETCH_INSTRUCTIONS
  151. esp_err_t esp_spiram_enable_instruction_access(void)
  152. {
  153. uint32_t pages_in_flash = 0;
  154. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_IBUS0, &page0_mapped);
  155. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_IBUS1, &page0_mapped);
  156. if ((pages_in_flash + pages_for_flash) > (SPIRAM_SIZE >> 16)) {
  157. 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));
  158. return ESP_FAIL;
  159. }
  160. ESP_EARLY_LOGI(TAG, "Instructions copied and mapped to SPIRAM");
  161. uint32_t instr_mmu_offset = ((uint32_t)&_instruction_reserved_start & 0xFFFFFF)/MMU_PAGE_SIZE;
  162. uint32_t mmu_value = *(volatile uint32_t *)(DR_REG_MMU_TABLE + PRO_CACHE_IBUS0_MMU_START + instr_mmu_offset*sizeof(uint32_t));
  163. mmu_value &= MMU_ADDRESS_MASK;
  164. instr_flash2spiram_offs = mmu_value - pages_for_flash;
  165. ESP_EARLY_LOGV(TAG, "Instructions from flash page%d copy to SPIRAM page%d, Offset: %d", mmu_value, pages_for_flash, instr_flash2spiram_offs);
  166. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_IBUS0, IRAM0_ADDRESS_LOW, pages_for_flash, &page0_page);
  167. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_IBUS1, IRAM1_ADDRESS_LOW, pages_for_flash, &page0_page);
  168. instrcution_in_spiram = 1;
  169. return ESP_OK;
  170. }
  171. #endif
  172. #if CONFIG_SPIRAM_RODATA
  173. esp_err_t esp_spiram_enable_rodata_access(void)
  174. {
  175. uint32_t pages_in_flash = 0;
  176. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_IBUS2, &page0_mapped);
  177. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_DBUS0, &page0_mapped);
  178. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_DBUS1, &page0_mapped);
  179. pages_in_flash += Cache_Count_Flash_Pages(PRO_CACHE_DBUS2, &page0_mapped);
  180. if ((pages_in_flash + pages_for_flash) > (SPIRAM_SIZE >> 16)) {
  181. ESP_EARLY_LOGE(TAG, "SPI RAM space not enough for the read only data.");
  182. return ESP_FAIL;
  183. }
  184. ESP_EARLY_LOGI(TAG, "Read only data copied and mapped to SPIRAM");
  185. uint32_t rodata_mmu_offset = ((uint32_t)&_rodata_reserved_start & 0xFFFFFF)/MMU_PAGE_SIZE;
  186. uint32_t mmu_value = *(volatile uint32_t *)(DR_REG_MMU_TABLE + PRO_CACHE_IBUS2_MMU_START + rodata_mmu_offset*sizeof(uint32_t));
  187. mmu_value &= MMU_ADDRESS_MASK;
  188. rodata_flash2spiram_offs = mmu_value - pages_for_flash;
  189. ESP_EARLY_LOGV(TAG, "Rodata from flash page%d copy to SPIRAM page%d, Offset: %d", mmu_value, pages_for_flash, rodata_flash2spiram_offs);
  190. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_IBUS2, DROM0_ADDRESS_LOW, pages_for_flash, &page0_page);
  191. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_DBUS0, DRAM0_ADDRESS_LOW, pages_for_flash, &page0_page);
  192. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_DBUS1, DRAM1_ADDRESS_LOW, pages_for_flash, &page0_page);
  193. pages_for_flash = Cache_Flash_To_SPIRAM_Copy(PRO_CACHE_DBUS2, DPORT_ADDRESS_LOW, pages_for_flash, &page0_page);
  194. rodata_in_spiram = 1;
  195. return ESP_OK;
  196. }
  197. #endif
  198. #if CONFIG_SPIRAM_FETCH_INSTRUCTIONS
  199. void instruction_flash_page_info_init(void)
  200. {
  201. uint32_t instr_page_cnt = ((uint32_t)&_instruction_reserved_end - SOC_IROM_LOW + MMU_PAGE_SIZE - 1)/MMU_PAGE_SIZE;
  202. uint32_t instr_mmu_offset = ((uint32_t)&_instruction_reserved_start & 0xFFFFFF)/MMU_PAGE_SIZE;
  203. instr_start_page = *(volatile uint32_t *)(DR_REG_MMU_TABLE + PRO_CACHE_IBUS0_MMU_START + instr_mmu_offset*sizeof(uint32_t));
  204. instr_start_page &= MMU_ADDRESS_MASK;
  205. instr_end_page = instr_start_page + instr_page_cnt - 1;
  206. }
  207. uint32_t IRAM_ATTR instruction_flash_start_page_get(void)
  208. {
  209. return instr_start_page;
  210. }
  211. uint32_t IRAM_ATTR instruction_flash_end_page_get(void)
  212. {
  213. return instr_end_page;
  214. }
  215. int IRAM_ATTR instruction_flash2spiram_offset(void)
  216. {
  217. return instr_flash2spiram_offs;
  218. }
  219. #endif
  220. #if CONFIG_SPIRAM_RODATA
  221. void rodata_flash_page_info_init(void)
  222. {
  223. uint32_t rodata_page_cnt = ((uint32_t)&_rodata_reserved_end - SOC_DROM_LOW + MMU_PAGE_SIZE - 1)/MMU_PAGE_SIZE;
  224. uint32_t rodata_mmu_offset = ((uint32_t)&_rodata_reserved_start & 0xFFFFFF)/MMU_PAGE_SIZE;
  225. rodata_start_page = *(volatile uint32_t *)(DR_REG_MMU_TABLE + PRO_CACHE_IBUS2_MMU_START + rodata_mmu_offset*sizeof(uint32_t));
  226. rodata_start_page &= MMU_ADDRESS_MASK;
  227. rodata_end_page = rodata_start_page + rodata_page_cnt - 1;
  228. }
  229. uint32_t IRAM_ATTR rodata_flash_start_page_get(void)
  230. {
  231. return rodata_start_page;
  232. }
  233. uint32_t IRAM_ATTR rodata_flash_end_page_get(void)
  234. {
  235. return rodata_end_page;
  236. }
  237. int IRAM_ATTR rodata_flash2spiram_offset(void)
  238. {
  239. return rodata_flash2spiram_offs;
  240. }
  241. #endif
  242. esp_err_t esp_spiram_init(void)
  243. {
  244. esp_err_t r;
  245. r = psram_enable(PSRAM_SPEED, PSRAM_MODE);
  246. if (r != ESP_OK) {
  247. #if CONFIG_SPIRAM_IGNORE_NOTFOUND
  248. ESP_EARLY_LOGE(TAG, "SPI RAM enabled but initialization failed. Bailing out.");
  249. #endif
  250. return r;
  251. }
  252. spiram_inited=true;
  253. #if (CONFIG_SPIRAM_SIZE != -1)
  254. if (esp_spiram_get_size()!=CONFIG_SPIRAM_SIZE) {
  255. ESP_EARLY_LOGE(TAG, "Expected %dKiB chip but found %dKiB chip. Bailing out..", CONFIG_SPIRAM_SIZE/1024, esp_spiram_get_size()/1024);
  256. return ESP_ERR_INVALID_SIZE;
  257. }
  258. #endif
  259. ESP_EARLY_LOGI(TAG, "Found %dMBit SPI RAM device",
  260. (esp_spiram_get_size()*8)/(1024*1024));
  261. ESP_EARLY_LOGI(TAG, "SPI RAM mode: %s", PSRAM_SPEED == PSRAM_CACHE_S40M ? "sram 40m" : \
  262. PSRAM_SPEED == PSRAM_CACHE_S80M ? "sram 80m" : "sram 20m");
  263. ESP_EARLY_LOGI(TAG, "PSRAM initialized, cache is in %s mode.", \
  264. (PSRAM_MODE==PSRAM_VADDR_MODE_EVENODD)?"even/odd (2-core)": \
  265. (PSRAM_MODE==PSRAM_VADDR_MODE_LOWHIGH)?"low/high (2-core)": \
  266. (PSRAM_MODE==PSRAM_VADDR_MODE_NORMAL)?"normal (1-core)":"ERROR");
  267. return ESP_OK;
  268. }
  269. esp_err_t esp_spiram_add_to_heapalloc(void)
  270. {
  271. uint32_t size_for_flash = (pages_for_flash << 16);
  272. intptr_t vaddr;
  273. ESP_EARLY_LOGI(TAG, "Adding pool of %dK of external SPI memory to heap allocator", (SPIRAM_SIZE - (pages_for_flash << 16))/1024);
  274. //Add entire external RAM region to heap allocator. Heap allocator knows the capabilities of this type of memory, so there's
  275. //no need to explicitly specify them.
  276. if (SPIRAM_SIZE <= DRAM0_DRAM1_DPORT_CACHE_SIZE) {
  277. /* cache size <= 10MB + 512KB, map DRAM0, DRAM1, DPORT bus */
  278. vaddr = SPIRAM_SMALL_SIZE_MAP_VADDR;
  279. return heap_caps_add_region(vaddr + size_for_flash, vaddr + SPIRAM_SMALL_SIZE_MAP_SIZE - 1);
  280. }
  281. vaddr = DPORT_CACHE_ADDRESS_LOW;
  282. Cache_Dbus_MMU_Set(MMU_ACCESS_SPIRAM, vaddr, SPIRAM_SMALL_SIZE_MAP_PADDR, 64, DRAM0_DRAM1_DPORT_CACHE_SIZE >> 16, 0);
  283. if (size_for_flash <= SPIRAM_SIZE_EXC_DRAM0_DRAM1_DPORT) {
  284. return heap_caps_add_region(vaddr, vaddr + DRAM0_DRAM1_DPORT_CACHE_SIZE - 1);
  285. }
  286. // Largest size
  287. return heap_caps_add_region(vaddr + size_for_flash, vaddr + DRAM0_DRAM1_DPORT_CACHE_SIZE -1);
  288. }
  289. static uint8_t *dma_heap;
  290. esp_err_t esp_spiram_reserve_dma_pool(size_t size) {
  291. if (size==0) return ESP_OK; //no-op
  292. ESP_EARLY_LOGI(TAG, "Reserving pool of %dK of internal memory for DMA/internal allocations", size/1024);
  293. dma_heap=heap_caps_malloc(size, MALLOC_CAP_DMA|MALLOC_CAP_INTERNAL);
  294. if (!dma_heap) return ESP_ERR_NO_MEM;
  295. uint32_t caps[]={MALLOC_CAP_DMA|MALLOC_CAP_INTERNAL, 0, MALLOC_CAP_8BIT|MALLOC_CAP_32BIT};
  296. return heap_caps_add_region_with_caps(caps, (intptr_t) dma_heap, (intptr_t) dma_heap+size-1);
  297. }
  298. size_t esp_spiram_get_size(void)
  299. {
  300. if (!spiram_inited) {
  301. ESP_EARLY_LOGE(TAG, "SPI RAM not initialized");
  302. abort();
  303. }
  304. psram_size_t size=psram_get_size();
  305. if (size==PSRAM_SIZE_16MBITS) return 2*1024*1024;
  306. if (size==PSRAM_SIZE_32MBITS) return 4*1024*1024;
  307. if (size==PSRAM_SIZE_64MBITS) return 8*1024*1024;
  308. return CONFIG_SPIRAM_SIZE;
  309. }
  310. /*
  311. 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,
  312. otherwise it will get lost. For now, we just read 64/128K of random PSRAM memory to do this.
  313. */
  314. void IRAM_ATTR esp_spiram_writeback_cache(void)
  315. {
  316. extern void Cache_WriteBack_All(void);
  317. Cache_WriteBack_All();
  318. }
  319. #endif