Skip to content

cloud-kernel
cloud-kernel

openanolis / cloud-kernel
大约 1 年 前同步成功

通知 158
Star 36
Fork 7
cloud-kernel
cloud-kernel
切换分支/标签
  1. 06 10月, 2009 1 次提交
    • J
      OMAP3: PM: Prevent hang in prcm_interrupt_handler · 77da2d91
      由 Jon Hunter 提交于 
      There are two scenarios where a race condition could result in a hang
in the prcm_interrupt handler. These are:

1). Waiting for PRM_IRQSTATUS_MPU register to clear.
Bit 0 of the PRM_IRQSTATUS_MPU register indicates that a wake-up event
is pending for the MPU. This bit can only be cleared if the all the
wake-up events latched in the various PM_WKST_x registers have been
cleared. If a wake-up event occurred during the processing of the prcm
interrupt handler, after the corresponding PM_WKST_x register was
checked but before the PRM_IRQSTATUS_MPU was cleared, then the CPU
would be stuck forever waiting for bit 0 in PRM_IRQSTATUS_MPU to be
cleared.

2). Waiting for the PM_WKST_x register to clear.
Some power domains have more than one wake-up source. The PM_WKST_x
registers indicate the source of a wake-up event and need to be cleared
after a wake-up event occurs. When the PM_WKST_x registers are read and
before they are cleared, it is possible that another wake-up event
could occur causing another bit to be set in one of the PM_WKST_x
registers. If this did occur after reading a PM_WKST_x register then
the CPU would miss this event and get stuck forever in a loop waiting
for that PM_WKST_x register to clear.

This patch address the above race conditions that would result in a
hang.
Signed-off-by: NJon Hunter <jon-hunter@ti.com>
Reviewed-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>
      77da2d91
  3. 28 9月, 2009 8 次提交
  5. 27 9月, 2009 22 次提交
  7. 26 9月, 2009 9 次提交