Hi
I tried to turn on encryption in BL31. And, I met some trouble.
Here is my code.
``` static struct plat_io_policy policies[] = { ... [BL31_IMAGE_ID] = {&enc_dev_handle, &bl31_uuid_spec, check_enc_fip}, .... [ENC_IMAGE_ID] = {&fip_dev_handle, NULL, check_fip} }
int plat_get_image_source(...) { ... policy = &policies[image_id]; ret = policy->check[policy->image_spec]; ... }
static int check_fip(const uintptr_t spec) { int ret;
ret = io_dev_open(fip_dev_con, (uintptr_t)NULL, &fip_dev_handle);
if (ret) { ERROR("io_dev_open failed for FIP (%d)\n", ret); return ret; }
ret = io_dev_init(fip_dev_handle, fip_image_id); if (ret) { ERROR("io_dev_init failed for FIP image id %lu (%d)\n", fip_image_id, ret); io_dev_close(fip_dev_handle); } return ret; }
static int check_enc_fip(const uintptr_t spec) { int result; uintptr_t local_image_handle;
/* See if a Firmware Image Package is available */ result = io_dev_open(enc_dev_con, (uintptr_t)NULL, &enc_dev_handle); if (result) { ERROR("io_dev_open failed for FIP (%d)\n", result); return result; }
result = io_dev_init(enc_dev_handle, (uintptr_t)ENC_IMAGE_ID); if (result != 0) return result; return result; } ```
But, I can't boot successfully. Below is log. ``` INFO: Image id=3 loaded: 0x40800000 - 0x4080e299 INFO: BL2: Loading image id 5 WARNING: ===== allocate_dev_info 1 ===== WARNING: ==== -12 ==== ERROR: io_dev_open failed for FIP (-12) ERROR: Image id 11 open failed with -12 WARNING: Failed to obtain reference to image id=11 (-12) ERROR: BL2: Failed to load image id 5 (-12) ```
And, I found root cause in `allocate_dev_info` and `free_dev_info` in `drivers/io/io_fip.c` In `allocate_dev_info`, there is a count, `fip_dev_count`, increasing by 1 after calling `fip_dev_open` There is a check. The value of MAX_FIP_DEVICES is 1. ``` if (fip_dev_count < (unsigned int)MAX_FIP_DEVICES) { unsigned int index = 0;
result = find_first_fip_state(0, &index); assert(result == 0); /* initialize dev_info */ dev_info_pool[index].funcs = &fip_dev_funcs; dev_info_pool[index].info = (uintptr_t)&state_pool[index]; *dev_info = &dev_info_pool[index]; ++fip_dev_count; } ``` And, in `fip_dev_close`, The `fip_dev_count` will be decreased by 1.
However, The root casue is it call fip_dev_open but not calling fip_dev_close. It cause the `fip_dev_count` not be decreased by 1.
Now, I have two solution. 1. Increasing the MAX_FIP_DEVICES, it will be working. 2. Add the io_dev_close in `enc_dev_close` in `driver/io_/io_encrypted.c`. And, it will call the fip_dev_close. It will be working.
Do you have any idea in this solution ? Which solution is more general ?
Thanks !