stm32/flashbdev: Fix bug with L4 block cache, dereferencing block size.

The code was dereferencing 0x800 and loading a value from there, trying to use a literal value (not address) defined in the linker script (_ram_fs_cache_block_size) which was 0x800.
micropython · Jul 19, 2018 · a8736e5 · a8736e5
1 parent 3ffcef8
commit a8736e5
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Showing 4 changed files with 9 additions and 8 deletions.
diff --git a/ports/stm32/boards/stm32l476xe.ld b/ports/stm32/boards/stm32l476xe.ld
@@ -25,7 +25,7 @@ _estack = ORIGIN(RAM) + LENGTH(RAM);
 
 /* RAM extents for the garbage collector */
 _ram_fs_cache_start = ORIGIN(FS_CACHE);
-_ram_fs_cache_block_size = LENGTH(FS_CACHE);
+_ram_fs_cache_end = ORIGIN(FS_CACHE) + LENGTH(FS_CACHE);
 _ram_start = ORIGIN(RAM);
 _ram_end = ORIGIN(RAM) + LENGTH(RAM);
 _heap_start = _ebss; /* heap starts just after statically allocated memory */

diff --git a/ports/stm32/boards/stm32l476xg.ld b/ports/stm32/boards/stm32l476xg.ld
@@ -25,7 +25,7 @@ _estack = ORIGIN(RAM) + LENGTH(RAM);
 
 /* RAM extents for the garbage collector */
 _ram_fs_cache_start = ORIGIN(FS_CACHE);
-_ram_fs_cache_block_size = LENGTH(FS_CACHE);
+_ram_fs_cache_end = ORIGIN(FS_CACHE) + LENGTH(FS_CACHE);
 _ram_start = ORIGIN(RAM);
 _ram_end = ORIGIN(RAM) + LENGTH(RAM);
 _heap_start = _ebss; /* heap starts just after statically allocated memory */

diff --git a/ports/stm32/boards/stm32l496xg.ld b/ports/stm32/boards/stm32l496xg.ld
@@ -25,7 +25,7 @@ _estack = ORIGIN(RAM) + LENGTH(RAM) + LENGTH(SRAM2);
 
 /* RAM extents for the garbage collector */
 _ram_fs_cache_start = ORIGIN(FS_CACHE);
-_ram_fs_cache_block_size = LENGTH(FS_CACHE);
+_ram_fs_cache_end = ORIGIN(FS_CACHE) + LENGTH(FS_CACHE);
 _ram_start = ORIGIN(RAM);
 _ram_end = ORIGIN(RAM) + LENGTH(RAM) + LENGTH(SRAM2);
 _heap_start = _ebss; /* heap starts just after statically allocated memory */

diff --git a/ports/stm32/flashbdev.c b/ports/stm32/flashbdev.c
@@ -95,14 +95,15 @@ STATIC byte flash_cache_mem[0x4000] __attribute__((aligned(4))); // 16k
 
 #elif defined(STM32L475xx) || defined(STM32L476xx) || defined(STM32L496xx)
 
+// The STM32L475/6 doesn't have CCRAM, so we use the 32K SRAM2 for this, although
+// actual location and size is defined by the linker script.
 extern uint8_t _flash_fs_start;
 extern uint8_t _flash_fs_end;
-extern uint32_t _ram_fs_cache_start[2048 / 4];
-extern uint32_t _ram_fs_cache_block_size;
+extern uint8_t _ram_fs_cache_start[]; // size determined by linker file
+extern uint8_t _ram_fs_cache_end[];
 
-// The STM32L475/6 doesn't have CCRAM, so we use the 32K SRAM2 for this.
-#define CACHE_MEM_START_ADDR (&_ram_fs_cache_start)       // End of SRAM2 RAM segment-2k
-#define FLASH_SECTOR_SIZE_MAX (_ram_fs_cache_block_size)  // 2k max
+#define CACHE_MEM_START_ADDR ((uintptr_t)&_ram_fs_cache_start[0])
+#define FLASH_SECTOR_SIZE_MAX (&_ram_fs_cache_end[0] - &_ram_fs_cache_start[0]) // 2k max
 #define FLASH_MEM_SEG1_START_ADDR ((long)&_flash_fs_start)
 #define FLASH_MEM_SEG1_NUM_BLOCKS ((&_flash_fs_end - &_flash_fs_start) / 512)