Merge pull request #773 from Daft-Freak/qspi-32-bytes-erratum

stm32: work around QSPI failing to read the last 32 bytes
32blit · Aug 8, 2022 · 6e516d7 · 6e516d7
2 parents b656fa3 + bedf052
commit 6e516d7
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/32blit-stm32/Src/quadspi.c b/32blit-stm32/Src/quadspi.c
@@ -33,7 +33,10 @@ void MX_QUADSPI_Init(void)
   hqspi.Init.ClockPrescaler = 2;
   hqspi.Init.FifoThreshold = 1;
   hqspi.Init.SampleShifting = QSPI_SAMPLE_SHIFTING_NONE;
-  hqspi.Init.FlashSize = QSPI_FLASH_SIZE;
+
+  // Use a flash size 2x what we should to avoid "Memory-mapped read of last memory byte fails"
+  // (due to prefetch, it's actually the last 32 bytes)
+  hqspi.Init.FlashSize = QSPI_FLASH_SIZE + 1;
   hqspi.Init.ChipSelectHighTime = QSPI_CS_HIGH_TIME_1_CYCLE;
   hqspi.Init.ClockMode = QSPI_CLOCK_MODE_3;
   hqspi.Init.FlashID = QSPI_FLASH_ID_2;