On Tue, Mar 02, 2021 at 12:09:21AM +0000, Yoo, Jae Hyun wrote:
-----Original Message----- From: Joel Stanley joel@jms.id.au Sent: Monday, March 1, 2021 2:44 PM To: Greg Kroah-Hartman gregkh@linuxfoundation.org; John Wang wangzhiqiang.bj@bytedance.com; Yoo, Jae Hyun jae.hyun.yoo@intel.com Cc: Linux Kernel Mailing List linux-kernel@vger.kernel.org; stable@vger.kernel.org; Vernon Mauery vernon.mauery@linux.intel.com; Sasha Levin sashal@kernel.org Subject: Re: [PATCH 4.19 055/247] soc: aspeed: snoop: Add clock control logic
On Mon, 1 Mar 2021 at 16:37, Greg Kroah-Hartman gregkh@linuxfoundation.org wrote:
From: Jae Hyun Yoo jae.hyun.yoo@intel.com
[ Upstream commit 3f94cf15583be554df7aaa651b8ff8e1b68fbe51 ]
If LPC SNOOP driver is registered ahead of lpc-ctrl module, LPC SNOOP block will be enabled without heart beating of LCLK until lpc-ctrl enables the LCLK. This issue causes improper handling on host interrupts when the host sends interrupt in that time frame. Then kernel eventually forcibly disables the interrupt with dumping stack and printing a 'nobody cared this irq' message out.
To prevent this issue, all LPC sub-nodes should enable LCLK individually so this patch adds clock control logic into the LPC SNOOP driver.
Jae, John; with this backported do we need to also provide a corresponding device tree change for the stable tree, otherwise this driver will no longer probe?
Right. The second patch https://lore.kernel.org/linux-arm-kernel/20201208091748.1920-2-wangzhiqiang.... John submitted should be applied to stable tree too to make this module be probed correctly.
Now queued up, thanks.
greg k-h