bus: mhi: core: Skip RDDM download for unknown execution environment

If MHI is unable to determine the execution environment during
the panic path, host must skip the RDDM download. This can happen
if the BHI offset read or the BHI_EXECENV register read fails
indicating that the underlying transport is unresponsive. Hence,
there is no need to trigger an RDDM using SYSERR or request an
SOC reset.

Suggested-by: Hemant Kumar <hemantk@codeaurora.org>
Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

diff --git a/drivers/bus/mhi/core/boot.c b/drivers/bus/mhi/core/boot.c
index 16244cc8fbe75dfc8cd42bc8be3b9d4fa71d146c..6f0cfb9922b45ad75dcce3ebc5083979f624c31c 100644 (file)
--- a/drivers/bus/mhi/core/boot.c
+++ b/drivers/bus/mhi/core/boot.c
@@ -92,6 +92,9 @@ static int __mhi_download_rddm_in_panic(struct mhi_controller *mhi_cntrl)
         * image download completion.
         */
        ee = mhi_get_exec_env(mhi_cntrl);
+       if (ee == MHI_EE_MAX)
+               goto error_exit_rddm;
+
        if (ee != MHI_EE_RDDM) {
                dev_dbg(dev, "Trigger device into RDDM mode using SYS ERR\n");
                mhi_set_mhi_state(mhi_cntrl, MHI_STATE_SYS_ERR);
@@ -139,10 +142,12 @@ static int __mhi_download_rddm_in_panic(struct mhi_controller *mhi_cntrl)
        ee = mhi_get_exec_env(mhi_cntrl);
        ret = mhi_read_reg(mhi_cntrl, base, BHIE_RXVECSTATUS_OFFS, &rx_status);
 
-       dev_err(dev, "Did not complete RDDM transfer\n");
-       dev_err(dev, "Current EE: %s\n", TO_MHI_EXEC_STR(ee));
        dev_err(dev, "RXVEC_STATUS: 0x%x\n", rx_status);
 
+error_exit_rddm:
+       dev_err(dev, "RDDM transfer failed. Current EE: %s\n",
+               TO_MHI_EXEC_STR(ee));
+
        return -EIO;
 }