Linux-ARM-Kernel Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Francesco Dolcini <francesco@dolcini.it>
To: bhelgaas@google.com, hongxing.zhu@oss.nxp.com,
	linux-pci@vger.kernel.org, Richard Zhu <hongxing.zhu@nxp.com>
Cc: frank.li@nxp.com, l.stach@pengutronix.de, lpieralisi@kernel.org,
	kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org,
	s.hauer@pengutronix.de, kernel@pengutronix.de,
	festevam@gmail.com, linux-arm-kernel@lists.infradead.org,
	imx@lists.linux.dev, linux-kernel@vger.kernel.org,
	regressions@lists.linux.dev
Subject: Re: [PATCH v2] PCI: imx6: Fix i.MX6Q/DL boot hang by separating PHY power and reference clock control
Date: Tue, 14 Jul 2026 14:51:26 +0200	[thread overview]
Message-ID: <20260714125126.GA84291@francesco-nb> (raw)
In-Reply-To: <20260708035928.580236-2-hongxing.zhu@oss.nxp.com>

Hello,

On Wed, Jul 08, 2026 at 11:59:27AM +0800, hongxing.zhu@oss.nxp.com wrote:
> From: Richard Zhu <hongxing.zhu@nxp.com>
> 
> Commit 610fa91d9863 ("PCI: imx6: Assert PERST# before enabling regulators")
> introduced a boot hang on i.MX6Q/DL variants by changing the initialization
> sequence.
> 
> The issue stems from coupling PHY power (TEST_PD) and reference clock
> (REF_CLK_EN) control in imx6q_pcie_enable_ref_clk(). When these are
> managed together, the timing between PHY power-up and reference clock
> enablement cannot be properly controlled, leading to initialization
> failures.
> 
> Fix this by separating the two concerns:
> 
> - Move PHY power control (TEST_PD) to imx6q_pcie_core_reset() where it
>   logically belongs with reset operations. This ensures PHY power state
>   is managed as part of the core reset sequence.
> 
> - Update imx6qp_pcie_core_reset() to call imx6q_pcie_core_reset() for
>   shared PHY power management, avoiding code duplication.
> 
> - Make imx6q_pcie_enable_ref_clk() responsible only for reference clock
>   (REF_CLK_EN) control, simplifying its purpose.
> 
> - Remove the 10us delay workaround from imx6q_pcie_enable_ref_clk() as
>   proper sequencing is now handled by the core_reset functions.
> 
> This refactoring ensures PHY power is controlled during reset
> operations, fixing the boot hang while improving code maintainability.
> 
> Fixes: 610fa91d9863 ("PCI: imx6: Assert PERST# before enabling regulators")
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>

What's the plan with this? 610fa91d9863 ("PCI: imx6: Assert PERST# before enabling regulators")
introduces a severe regression with boards not booting at all.

As of now we are not able to test anything, and our CI is completely
blind on any other issue that linux 7.2 might have introduced.

Is the plan to merge this, or to revert the commit? Any timeline?

Francesco




  parent reply	other threads:[~2026-07-14 12:51 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-08  3:59 [PATCH v2] PCI: imx6: Add runtime PM support for i.MX95 hongxing.zhu
2026-07-08  3:59 ` [PATCH v2] PCI: imx6: Fix i.MX6Q/DL boot hang by separating PHY power and reference clock control hongxing.zhu
2026-07-08 15:28   ` Frank Li
2026-07-14 12:51   ` Francesco Dolcini [this message]
2026-07-08  3:59 ` [PATCH v2] PCI: imx6: Update MPLLB bandwidth to improve i.MX95 Gen3 PCIe stability hongxing.zhu
2026-07-08 15:19   ` Frank Li
2026-07-09  7:55     ` Hongxing Zhu (OSS)
2026-07-09 15:08       ` Frank Li

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260714125126.GA84291@francesco-nb \
    --to=francesco@dolcini.it \
    --cc=bhelgaas@google.com \
    --cc=festevam@gmail.com \
    --cc=frank.li@nxp.com \
    --cc=hongxing.zhu@nxp.com \
    --cc=hongxing.zhu@oss.nxp.com \
    --cc=imx@lists.linux.dev \
    --cc=kernel@pengutronix.de \
    --cc=kwilczynski@kernel.org \
    --cc=l.stach@pengutronix.de \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=lpieralisi@kernel.org \
    --cc=mani@kernel.org \
    --cc=regressions@lists.linux.dev \
    --cc=robh@kernel.org \
    --cc=s.hauer@pengutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox