On 5/6/2025 8:49 AM, Muhammad Usama Anjum wrote:
Fix dma_direct_alloc() failure at resume time during bhie_table
allocation because of memory pressure. There is a report where at
resume time, the memory from the dma doesn't get allocated and MHI
fails to re-initialize.
To fix it, don't free the memory at power down during suspend /
hibernation. Instead, use the same allocated memory again after every
resume / hibernation. This patch has been tested with resume and
hibernation both.
The rddm is of constant size for a given hardware. While the fbc_image
size depends on the firmware. If the firmware changes, we'll free and
allocate new memory for it.
Why is it valid to load new firmware as a result of suspend? I don't
users would expect that.
diff --git a/drivers/bus/mhi/host/boot.c b/drivers/bus/mhi/host/boot.c
index efa3b6dddf4d2..bc8459798bbee 100644
--- a/drivers/bus/mhi/host/boot.c
+++ b/drivers/bus/mhi/host/boot.c
@@ -584,10 +584,17 @@ void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl)
* device transitioning into MHI READY state
*/
if (fw_load_type == MHI_FW_LOAD_FBC) {
Why is this FBC specific?
- ret = mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->fbc_image, fw_sz);
- if (ret) {
- release_firmware(firmware);
- goto error_fw_load;
+ if (mhi_cntrl->fbc_image && fw_sz != mhi_cntrl->prev_fw_sz) {
+ mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->fbc_image);
+ mhi_cntrl->fbc_image = NULL;
+ }
+ if (!mhi_cntrl->fbc_image) {
+ ret = mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->fbc_image, fw_sz);
+ if (ret) {
+ release_firmware(firmware);
+ goto error_fw_load;
+ }
+ mhi_cntrl->prev_fw_sz = fw_sz;
}
/* Load the firmware into BHIE vec table */
diff --git a/drivers/bus/mhi/host/pm.c b/drivers/bus/mhi/host/pm.c
index e6c3ff62bab1d..107d71b4cc51a 100644
--- a/drivers/bus/mhi/host/pm.c
+++ b/drivers/bus/mhi/host/pm.c
@@ -1259,10 +1259,19 @@ void mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful)
}
EXPORT_SYMBOL_GPL(mhi_power_down);
+static void __mhi_power_down_unprepare_keep_dev(struct mhi_controller *mhi_cntrl)
+{
+ mhi_cntrl->bhi = NULL;
+ mhi_cntrl->bhie = NULL;
Why?
+
+ mhi_deinit_dev_ctxt(mhi_cntrl);
+}
