MGS-4151-6 [#imx-1166] merge register read fix for clock-off

CL165804 fix read register when internal clock off 1. For
 shared IRQ, read register may be called and that's not our
 irq. 2. In some condition, when ISR handled normal FE/PE,
 PM thread could trun off internal clock before ISR read
 register of async FE. And then IRQ handler will call read
 register with internal clock off. So here we need to skip
 read in such case. This is simple fix.

cherry-pick patch:
6.2.4.p3-0019-CL165804-fix-read-register-when-internal-clock-off-1

Signed-off-by: Xianzhong <xianzhong.li@nxp.com>

1 files changed, 21 insertions, 2 deletions

diff --git a/drivers/mxc/gpu-viv/hal/os/linux/kernel/gc_hal_kernel_os.c b/drivers/mxc/gpu-viv/hal/os/linux/kernel/gc_hal_kernel_os.c
index dcf4daf5bae4..bc316b3c0acb 100644
--- a/drivers/mxc/gpu-viv/hal/os/linux/kernel/gc_hal_kernel_os.c
+++ b/drivers/mxc/gpu-viv/hal/os/linux/kernel/gc_hal_kernel_os.c
@@ -1597,6 +1597,8 @@ gckOS_ReadRegisterEx(
 {
     if (in_irq())
     {
+        uint32_t data;
+
         spin_lock(&Os->registerAccessLock);
 
         if (unlikely(Os->clockStates[Core] == gcvFALSE))
@@ -1604,12 +1606,29 @@ gckOS_ReadRegisterEx(
             spin_unlock(&Os->registerAccessLock);
 
             /*
-             * Read register when power off:
+             * Read register when external clock off:
              * 1. In shared IRQ, read register may be called and that's not our irq.
              */
             return gcvSTATUS_GENERIC_IO;
         }
 
+        data = readl(Os->device->registerBases[Core]);
+
+        if (unlikely((data & 0x3) == 0x3))
+        {
+            spin_unlock(&Os->registerAccessLock);
+
+            /*
+             * Read register when internal clock off:
+             * a. In shared IRQ, read register may be called and that's not our irq.
+             * b. In some condition, when ISR handled normal FE/PE, PM thread could
+             *    trun off internal clock before ISR read register of async FE. And
+             *    then IRQ handler will call read register with internal clock off.
+             *    So here we just skip for such case.
+             */
+            return gcvSTATUS_GENERIC_IO;
+        }
+
         *Data = readl((gctUINT8 *)Os->device->registerBases[Core] + Address);
         spin_unlock(&Os->registerAccessLock);
     }
@@ -1624,7 +1643,7 @@ gckOS_ReadRegisterEx(
             spin_unlock_irqrestore(&Os->registerAccessLock, flags);
 
             /*
-             * Read register when power off:
+             * Read register when external clock off:
              * 2. In non-irq context, register access should not be called,
              *    otherwise it's driver bug.
              */