| Message ID | 1641368602-20401-6-git-send-email-hongxing.zhu@nxp.com |
|---|---|
| State | New |
| Headers | show |
| Series | PCI: imx6: refine codes and add compliance tests mode support | expand |
Hi Richard, On Wed, Jan 5, 2022 at 5:12 AM Richard Zhu <hongxing.zhu@nxp.com> wrote: > > When PCIe PHY link never came up and vpcie regulator is present, there > would be following dump when try to put the regulator. > Add a new host_exit() callback for i.MX PCIe driver to disable this > regulator and fix this dump when link never came up. > > The driver should undo any enables it did itself, and not undo any > enables that anything else did which means it should never be basing > decisions on regulator_is_enabled(). > > To keep usage counter balance of the clocks, powers and so on. Do the > clock disable in the error handling after host_init too. > > imx6q-pcie 33800000.pcie: Phy link never came up > imx6q-pcie: probe of 33800000.pcie failed with error -110 Shouldn't we ignore the dw_pcie_wait_for_link() error? At least, this was the intention of 886a9c134755 ("PCI: dwc: Move link handling into common code"). > ------------[ cut here ]------------ > WARNING: CPU: 3 PID: 119 at drivers/regulator/core.c:2256 _regulator_put.part.0+0x14c/0x158 > Modules linked in: My concern is that this issue is still present in 5.15, which is LTS. You only address this problem in 5/6 and I am not sure if the previous patches could be applied to stable as they are cleanups. How can we fix this for 5.15 stable? Could you make a minimal fix as the first patch of the series and cleanup patches later?
> -----Original Message----- > From: Fabio Estevam <festevam@gmail.com> > Sent: Thursday, January 6, 2022 5:52 AM > To: Hongxing Zhu <hongxing.zhu@nxp.com> > Cc: Lucas Stach <l.stach@pengutronix.de>; Bjorn Helgaas > <bhelgaas@google.com>; Mark Brown <broonie@kernel.org>; > lorenzo.pieralisi@arm.com; jingoohan1@gmail.com; > stable@vger.kernel.org; linux-pci@vger.kernel.org; dl-linux-imx > <linux-imx@nxp.com>; linux-arm-kernel@lists.infradead.org; > linux-kernel@vger.kernel.org; kernel@pengutronix.de > Subject: Re: [PATCH v5 5/6] PCI: imx6: Fix the regulator dump when link > never came up > > Hi Richard, > > On Wed, Jan 5, 2022 at 5:12 AM Richard Zhu <hongxing.zhu@nxp.com> > wrote: > > > > When PCIe PHY link never came up and vpcie regulator is present, there > > would be following dump when try to put the regulator. > > Add a new host_exit() callback for i.MX PCIe driver to disable this > > regulator and fix this dump when link never came up. > > > > The driver should undo any enables it did itself, and not undo any > > enables that anything else did which means it should never be basing > > decisions on regulator_is_enabled(). > > > > To keep usage counter balance of the clocks, powers and so on. Do the > > clock disable in the error handling after host_init too. > > > > imx6q-pcie 33800000.pcie: Phy link never came up > > imx6q-pcie: probe of 33800000.pcie failed with error -110 > > Shouldn't we ignore the dw_pcie_wait_for_link() error? > > At least, this was the intention of 886a9c134755 ("PCI: dwc: Move link > handling into common code"). > > > ------------[ cut here ]------------ > > WARNING: CPU: 3 PID: 119 at drivers/regulator/core.c:2256 > _regulator_put.part.0+0x14c/0x158 > > Modules linked in: > > My concern is that this issue is still present in 5.15, which is LTS. > > You only address this problem in 5/6 and I am not sure if the previous > patches could be applied to stable as they are cleanups. > > How can we fix this for 5.15 stable? > > Could you make a minimal fix as the first patch of the series and cleanup > patches later? [Richard Zhu] Remove the stable kernel mail list firstly. Yes, you're right. It's difficult to merge this series back to 5.15 stable kernel, since the i.MX8MM PCIe support patch-set had been merged, and there are codes conflictions. How about continue proceed your previous fix firstly? https://patchwork.kernel.org/project/linux-pci/patch/20211104000202.4028036-1-festevam@gmail.com/ Then, I clean up the fix patch, and re-send my series later. Because that I still want to save power consumption as much as possible when link is down. BTW, please remove the timestamp in your patch if you agree this method, and resend your patch. Best Regards Richard Zhu
Hi Richard, On Thu, Jan 6, 2022 at 12:49 AM Hongxing Zhu <hongxing.zhu@nxp.com> wrote: > How about continue proceed your previous fix firstly? > https://patchwork.kernel.org/project/linux-pci/patch/20211104000202.4028036-1-festevam@gmail.com/ > Then, I clean up the fix patch, and re-send my series later. > Because that I still want to save power consumption as much as possible > when link is down. > BTW, please remove the timestamp in your patch if you agree this method, > and resend your patch. Sure, this sounds good. I have just sent a v2. Thanks
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c index 15908c184953..61b25f5cbf5c 100644 --- a/drivers/pci/controller/dwc/pci-imx6.c +++ b/drivers/pci/controller/dwc/pci-imx6.c @@ -369,8 +369,6 @@ static int imx6_pcie_attach_pd(struct device *dev) static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie) { - struct device *dev = imx6_pcie->pci->dev; - switch (imx6_pcie->drvdata->variant) { case IMX7D: case IMX8MQ: @@ -400,14 +398,6 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie) IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16); break; } - - if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) { - int ret = regulator_disable(imx6_pcie->vpcie); - - if (ret) - dev_err(dev, "failed to disable vpcie regulator: %d\n", - ret); - } } static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie) @@ -575,7 +565,7 @@ static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) struct device *dev = pci->dev; int ret, err; - if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) { + if (imx6_pcie->vpcie) { ret = regulator_enable(imx6_pcie->vpcie); if (ret) { dev_err(dev, "failed to enable vpcie regulator: %d\n", @@ -648,7 +638,7 @@ static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) return 0; err_clks: - if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) { + if (imx6_pcie->vpcie) { ret = regulator_disable(imx6_pcie->vpcie); if (ret) dev_err(dev, "failed to disable vpcie regulator: %d\n", @@ -905,7 +895,6 @@ static int imx6_pcie_start_link(struct dw_pcie *pci) dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n", dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG0), dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG1)); - imx6_pcie_reset_phy(imx6_pcie); return ret; } @@ -929,8 +918,29 @@ static int imx6_pcie_host_init(struct pcie_port *pp) return 0; } +static void imx6_pcie_host_exit(struct pcie_port *pp) +{ + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct device *dev = pci->dev; + struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci); + + imx6_pcie_reset_phy(imx6_pcie); + imx6_pcie_clk_disable(imx6_pcie); + switch (imx6_pcie->drvdata->variant) { + case IMX8MM: + if (phy_power_off(imx6_pcie->phy)) + dev_err(dev, "unable to power off phy\n"); + break; + default: + break; + } + if (imx6_pcie->vpcie) + regulator_disable(imx6_pcie->vpcie); +} + static const struct dw_pcie_host_ops imx6_pcie_host_ops = { .host_init = imx6_pcie_host_init, + .host_exit = imx6_pcie_host_exit, }; static const struct dw_pcie_ops dw_pcie_ops = {
When PCIe PHY link never came up and vpcie regulator is present, there would be following dump when try to put the regulator. Add a new host_exit() callback for i.MX PCIe driver to disable this regulator and fix this dump when link never came up. The driver should undo any enables it did itself, and not undo any enables that anything else did which means it should never be basing decisions on regulator_is_enabled(). To keep usage counter balance of the clocks, powers and so on. Do the clock disable in the error handling after host_init too. imx6q-pcie 33800000.pcie: Phy link never came up imx6q-pcie: probe of 33800000.pcie failed with error -110 ------------[ cut here ]------------ WARNING: CPU: 3 PID: 119 at drivers/regulator/core.c:2256 _regulator_put.part.0+0x14c/0x158 Modules linked in: CPU: 3 PID: 119 Comm: kworker/u8:2 Not tainted 5.13.0-rc7-next-20210625-94710-ge4e92b2588a3 #10 Hardware name: FSL i.MX8MM EVK board (DT) Workqueue: events_unbound async_run_entry_fn pstate: 80000005 (Nzcv daif -PAN -UAO -TCO BTYPE=--) pc : _regulator_put.part.0+0x14c/0x158 lr : regulator_put+0x34/0x48 sp : ffff8000122ebb30 x29: ffff8000122ebb30 x28: ffff800011be7000 x27: 0000000000000000 x26: 0000000000000000 x25: 0000000000000000 x24: ffff00000025f2bc x23: ffff00000025f2c0 x22: ffff00000025f010 x21: ffff8000122ebc18 x20: ffff800011e3fa60 x19: ffff00000375fd80 x18: 0000000000000010 x17: 000000040044ffff x16: 00400032b5503510 x15: 0000000000000108 x14: ffff0000003cc938 x13: 00000000ffffffea x12: 0000000000000000 x11: 0000000000000000 x10: ffff80001076ba88 x9 : ffff80001076a540 x8 : ffff00000025f2c0 x7 : ffff0000001f4450 x6 : ffff000000176cd8 x5 : ffff000003857880 x4 : 0000000000000000 x3 : ffff800011e3fe30 x2 : ffff0000003cc4c0 x1 : 0000000000000000 x0 : 0000000000000001 Call trace: _regulator_put.part.0+0x14c/0x158 regulator_put+0x34/0x48 devm_regulator_release+0x10/0x18 release_nodes+0x38/0x60 devres_release_all+0x88/0xd0 really_probe+0xd0/0x2e8 __driver_probe_device+0x74/0xd8 driver_probe_device+0x7c/0x108 __device_attach_driver+0x8c/0xd0 bus_for_each_drv+0x74/0xc0 __device_attach_async_helper+0xb4/0xd8 async_run_entry_fn+0x30/0x100 process_one_work+0x19c/0x320 worker_thread+0x48/0x418 kthread+0x14c/0x158 ret_from_fork+0x10/0x18 ---[ end trace 3664ca4a50ce849b ]--- Link: https://lore.kernel.org/r/20201105211159.1814485-11-robh@kernel.org Fixes: 886a9c134755 ("PCI: dwc: Move link handling into common code") Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com> --- drivers/pci/controller/dwc/pci-imx6.c | 36 +++++++++++++++++---------- 1 file changed, 23 insertions(+), 13 deletions(-)