| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <d577303de61fb060aa428898f5df1d0bc9be89b8.1535369231.git.leonard.crestez@nxp.com>
Date: Mon, 27 Aug 2018 14:28:37 +0300
From: Leonard Crestez <leonard.crestez@....com>
To: Lorenzo Pieralisi <lorenzo.pieralisi@....com>
Cc: Lucas Stach <l.stach@...gutronix.de>,
Andrey Smirnov <andrew.smirnov@...il.com>,
Richard Zhu <hongxing.zhu@....com>,
Anson Huang <Anson.Huang@....com>,
Philipp Zabel <p.zabel@...gutronix.de>,
Bjorn Helgaas <bhelgaas@...gle.com>,
Jingoo Han <jingoohan1@...il.com>,
Joao Pinto <Joao.Pinto@...opsys.com>,
Fabio Estevam <fabio.estevam@....com>,
Dong Aisheng <aisheng.dong@....com>, linux-imx@....com,
kernel@...gutronix.de, linux-pci@...r.kernel.org,
linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: [RESEND] PCI: imx: Initial imx7d pm support
On imx7d the pcie-phy power domain is turned off in suspend and this can
make the system hang after resume when attempting any read from PCI.
Fix this by adding minimal suspend/resume code from the nxp internal
tree. This will prepare for powering down on suspend and reset the block
on resume.
Code is only for imx7d but a very similar sequence can be used for
other socs.
The original author is mostly Richard Zhu <hongxing.zhu@....com>, this
patch adjusts the code to the upstream imx7d implemention using reset
controls and power domains.
Signed-off-by: Leonard Crestez <leonard.crestez@....com>
Reviewed-by: Lucas Stach <l.stach@...gutronix.de>
---
drivers/pci/controller/dwc/pci-imx6.c | 97 +++++++++++++++++++++++++--
1 file changed, 92 insertions(+), 5 deletions(-)
Resending after RC1 as suggested here: https://lkml.org/lkml/2018/8/8/496
This was initially sent together with a dts fix, that was already
accepted by Shawn: https://lkml.org/lkml/2018/8/21/529
Some dependencies in this area are complicated but as far as I know
including this patch without others should not break anything that was
not already broken. Since this is a patch for something that has never
worked before it should be treated as a feature not a bugfix.
I have a few other patches for imx pci but it's better to deal with them
separately. This initial patch adding suspend support is useful by
itself.
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 4a9a673b4777..65b6d1015723 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -540,10 +540,28 @@ static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie)
dev_err(dev, "Speed change timeout\n");
return -EINVAL;
}
+static void imx6_pcie_ltssm_enable(struct device *dev)
+{
+ struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
+
+ switch (imx6_pcie->variant) {
+ case IMX6Q:
+ case IMX6SX:
+ case IMX6QP:
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6Q_GPR12_PCIE_CTL_2,
+ IMX6Q_GPR12_PCIE_CTL_2);
+ break;
+ case IMX7D:
+ reset_control_deassert(imx6_pcie->apps_reset);
+ break;
+ }
+}
+
static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie)
{
struct dw_pcie *pci = imx6_pcie->pci;
struct device *dev = pci->dev;
u32 tmp;
@@ -558,15 +576,11 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie)
tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1;
dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp);
/* Start LTSSM. */
- if (imx6_pcie->variant == IMX7D)
- reset_control_deassert(imx6_pcie->apps_reset);
- else
- regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
- IMX6Q_GPR12_PCIE_CTL_2, 1 << 10);
+ imx6_pcie_ltssm_enable(dev);
ret = imx6_pcie_wait_for_link(imx6_pcie);
if (ret)
goto err_reset_phy;
@@ -680,10 +694,82 @@ static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie,
static const struct dw_pcie_ops dw_pcie_ops = {
.link_up = imx6_pcie_link_up,
};
+#ifdef CONFIG_PM_SLEEP
+static void imx6_pcie_ltssm_disable(struct device *dev)
+{
+ struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
+
+ switch (imx6_pcie->variant) {
+ case IMX6SX:
+ case IMX6QP:
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6Q_GPR12_PCIE_CTL_2, 0);
+ break;
+ case IMX7D:
+ reset_control_assert(imx6_pcie->apps_reset);
+ break;
+ default:
+ dev_err(dev, "ltssm_disable not supported\n");
+ }
+}
+
+static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
+{
+ clk_disable_unprepare(imx6_pcie->pcie);
+ clk_disable_unprepare(imx6_pcie->pcie_phy);
+ clk_disable_unprepare(imx6_pcie->pcie_bus);
+
+ if (imx6_pcie->variant == IMX7D) {
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
+ IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
+ }
+}
+
+static int imx6_pcie_suspend_noirq(struct device *dev)
+{
+ struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
+
+ if (imx6_pcie->variant != IMX7D)
+ return 0;
+
+ imx6_pcie_clk_disable(imx6_pcie);
+ imx6_pcie_ltssm_disable(dev);
+
+ return 0;
+}
+
+static int imx6_pcie_resume_noirq(struct device *dev)
+{
+ int ret;
+ struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
+ struct pcie_port *pp = &imx6_pcie->pci->pp;
+
+ if (imx6_pcie->variant != IMX7D)
+ return 0;
+
+ imx6_pcie_assert_core_reset(imx6_pcie);
+ imx6_pcie_init_phy(imx6_pcie);
+ imx6_pcie_deassert_core_reset(imx6_pcie);
+ dw_pcie_setup_rc(pp);
+
+ ret = imx6_pcie_establish_link(imx6_pcie);
+ if (ret < 0)
+ dev_info(dev, "pcie link is down after resume.\n");
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops imx6_pcie_pm_ops = {
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx6_pcie_suspend_noirq,
+ imx6_pcie_resume_noirq)
+};
+
static int imx6_pcie_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct dw_pcie *pci;
struct imx6_pcie *imx6_pcie;
@@ -846,10 +932,11 @@ static const struct of_device_id imx6_pcie_of_match[] = {
static struct platform_driver imx6_pcie_driver = {
.driver = {
.name = "imx6q-pcie",
.of_match_table = imx6_pcie_of_match,
.suppress_bind_attrs = true,
+ .pm = &imx6_pcie_pm_ops,
},
.probe = imx6_pcie_probe,
.shutdown = imx6_pcie_shutdown,
};
--
2.17.1
Powered by blists - more mailing lists