On 4/7/20 9:50 AM, Jeffrey Hugo wrote:
The MHI device may be in the syserr state when we attempt to init it in
power_up(). Since we have no local state, the handling is simple -
reset the device and wait for it to transition out of the reset state.
Signed-off-by: Jeffrey Hugo <jhugo@xxxxxxxxxxxxxx>
---
drivers/bus/mhi/core/pm.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index 52690cb..3285c9e 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -9,6 +9,7 @@
#include <linux/dma-direction.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
+#include <linux/iopoll.h>
#include <linux/list.h>
#include <linux/mhi.h>
#include <linux/module.h>
@@ -760,6 +761,7 @@ static void mhi_deassert_dev_wake(struct mhi_controller *mhi_cntrl,
int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
{
+ enum mhi_state state;
enum mhi_ee_type current_ee;
enum dev_st_transition next_state;
struct device *dev = &mhi_cntrl->mhi_dev->dev;
@@ -829,6 +831,24 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
goto error_bhi_offset;
}
+ state = mhi_get_mhi_state(mhi_cntrl);
+ if (state == MHI_STATE_SYS_ERR) {
+ mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET);
+ ret = readl_poll_timeout(mhi_cntrl->regs + MHICTRL, val,
+ !(val & MHICTRL_RESET_MASK), 1000,
+ mhi_cntrl->timeout_ms * 1000);
can we use this instead of polling because MSI is configures and int_vec
handler is registered
wait_event_timeout(mhi_cntrl->state_event,
MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state) ||
mhi_read_reg_field(mhi_cntrl, base, MHICTRL,
MHICTRL_RESET_MASK,
MHICTRL_RESET_SHIFT, &reset) || !reset ,
msecs_to_jiffies(mhi_cntrl->timeout_ms));
1) In case of MHI_PM_IN_FATAL_STATE we would not be accessing MHI reg
2) Consistent with current MHI driver code.
+ if (ret) {
+ dev_info(dev, "Failed to reset MHI due to syserr state\n");
+ goto error_bhi_offset;
+ }
+
+ /*
+ * device cleares INTVEC as part of RESET processing,
+ * re-program it
+ */
+ mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
+ }
+
/* Transition to next state */
next_state = MHI_IN_PBL(current_ee) ?
DEV_ST_TRANSITION_PBL : DEV_ST_TRANSITION_READY;
--
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