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fix jpeg eoi check for psram_mode (DMA) #777

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Merged
merged 2 commits into from
Aug 5, 2025
Merged

fix jpeg eoi check for psram_mode (DMA) #777

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cf96213
fix jpeg eoi check for psram_mode (DMA)
RubenKelevra Jul 22, 2025
7b9e4f7
Merge branch 'master' into bugfix/implement_jpeg_eoi_check_for_psram_dma
me-no-dev Aug 5, 2025
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38 changes: 37 additions & 1 deletion driver/cam_hal.c
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Original file line number Diff line number Diff line change
Expand Up @@ -69,6 +69,12 @@ static portMUX_TYPE g_psram_dma_lock = portMUX_INITIALIZER_UNLOCKED;
#define CAM_SOI_PROBE_BYTES 32
#endif

/* Number of bytes copied to SRAM for EOI validation when capturing
* directly to PSRAM. Tunable to probe more of the frame tail if needed. */
#ifndef CAM_EOI_PROBE_BYTES
#define CAM_EOI_PROBE_BYTES 32
#endif

/*
* PSRAM DMA may bypass the CPU cache. Always call esp_cache_msync() on the
* SOI probe region so cached reads see the data written by DMA.
Expand Down Expand Up @@ -669,7 +675,37 @@ camera_fb_t *cam_take(TickType_t timeout)

if (cam_obj->jpeg_mode) {
/* find the end marker for JPEG. Data after that can be discarded */
int offset_e = cam_verify_jpeg_eoi(dma_buffer->buf, dma_buffer->len);
int offset_e = -1;
if (cam_obj->psram_mode) {
size_t probe_len = dma_buffer->len;
if (probe_len > CAM_EOI_PROBE_BYTES) {
probe_len = CAM_EOI_PROBE_BYTES;
}
if (probe_len == 0) {
goto skip_eoi_check;
}
size_t line = dcache_line_size();
if (line == 0) {
line = 32; /* sane fallback */
}
uintptr_t addr = (uintptr_t)(dma_buffer->buf + dma_buffer->len - probe_len);
uintptr_t start = addr & ~(line - 1);
size_t sync_len = (probe_len + (addr - start) + line - 1) & ~(line - 1);
esp_cache_msync((void *)start, sync_len,
ESP_CACHE_MSYNC_FLAG_DIR_M2C | ESP_CACHE_MSYNC_FLAG_INVALIDATE);

uint8_t eoi_probe[CAM_EOI_PROBE_BYTES];
memcpy(eoi_probe, dma_buffer->buf + dma_buffer->len - probe_len, probe_len);
int off = cam_verify_jpeg_eoi(eoi_probe, probe_len);
if (off >= 0) {
offset_e = dma_buffer->len - probe_len + off;
}
} else {
offset_e = cam_verify_jpeg_eoi(dma_buffer->buf, dma_buffer->len);
}

skip_eoi_check:

if (offset_e >= 0) {
dma_buffer->len = offset_e + sizeof(JPEG_EOI_MARKER);
return dma_buffer;
Expand Down