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Pierre-Louis Bossart authored
The Cadence IP can be configured in two different ways to deal with CMD_IGNORED replies to broadcast commands. The CMD_ACCEPT bitfield controls whether the command is discarded or if the IP proceeds with the change (typically a bank switch or clock stop command). The existing code seems to be inconsistent: a) For some historical reason, we set this CMD_ACCEPT bitfield during the initialization, but we don't during a resume from a clock-stoppped state. b) In addition, the loop used in the clock-stop sequence is quite racy, it's possible that a device has lost sync but it's still tagged as ATTACHED. c) If somehow a Device loses sync and is unable to ack a broadcast command, we do not have an error handling mechanism anyways. The IP should go ahead and let the Device regain sync at a later time. Make sure the CMD_ACCEPT bit is always set. Signed-off-by:
Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Reviewed-by:
Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com> Reviewed-by:
Rander Wang <rander.wang@intel.com> Signed-off-by:
Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210511025247.25339-1-yung-chuan.liao@linux.intel.com Signed-off-by:
Vinod Koul <vkoul@kernel.org>
Pierre-Louis Bossart authoredThe Cadence IP can be configured in two different ways to deal with CMD_IGNORED replies to broadcast commands. The CMD_ACCEPT bitfield controls whether the command is discarded or if the IP proceeds with the change (typically a bank switch or clock stop command). The existing code seems to be inconsistent: a) For some historical reason, we set this CMD_ACCEPT bitfield during the initialization, but we don't during a resume from a clock-stoppped state. b) In addition, the loop used in the clock-stop sequence is quite racy, it's possible that a device has lost sync but it's still tagged as ATTACHED. c) If somehow a Device loses sync and is unable to ack a broadcast command, we do not have an error handling mechanism anyways. The IP should go ahead and let the Device regain sync at a later time. Make sure the CMD_ACCEPT bit is always set. Signed-off-by:
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