On Thu, Sep 10, 2020 at 11:56 AM Rob Herring [off-list ref] wrote:

On Mon, Aug 24, 2020 at 03:30:17PM -0400, Jim Quinlan wrote:

quoted

From: Jim Quinlan <redacted>

Broadcom Set-top (BrcmSTB) boards typically support S2, S3, and S5 suspend
and resume.  Now the PCIe driver may do so as well.

Signed-off-by: Jim Quinlan <redacted>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/pci/controller/pcie-brcmstb.c | 47 +++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index c2b3d2946a36..3d588ab7a6dd 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c

@@ -978,6 +978,47 @@ static void brcm_pcie_turn_off(struct brcm_pcie *pcie)
      brcm_pcie_bridge_sw_init_set(pcie, 1);
 }

+static int brcm_pcie_suspend(struct device *dev)
+{
+     struct brcm_pcie *pcie = dev_get_drvdata(dev);
+
+     brcm_pcie_turn_off(pcie);
+     clk_disable_unprepare(pcie->clk);
+
+     return 0;
+}
+
+static int brcm_pcie_resume(struct device *dev)
+{
+     struct brcm_pcie *pcie = dev_get_drvdata(dev);
+     void __iomem *base;
+     u32 tmp;
+     int ret;
+
+     base = pcie->base;
+     clk_prepare_enable(pcie->clk);
+
+     /* Take bridge out of reset so we can access the SERDES reg */
+     brcm_pcie_bridge_sw_init_set(pcie, 0);
+
+     /* SERDES_IDDQ = 0 */
+     tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
+     u32p_replace_bits(&tmp, 0, PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK);
+     writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
+
+     /* wait for serdes to be stable */
+     udelay(100);

Really needs to be a spinloop?

quoted

+
+     ret = brcm_pcie_setup(pcie);
+     if (ret)
+             return ret;
+
+     if (pcie->msi)
+             brcm_msi_set_regs(pcie->msi);
+
+     return 0;
+}
+
 static void __brcm_pcie_remove(struct brcm_pcie *pcie)
 {
      brcm_msi_remove(pcie);

@@ -1087,12 +1128,18 @@ static int brcm_pcie_probe(struct platform_device *pdev)

 MODULE_DEVICE_TABLE(of, brcm_pcie_match);

+static const struct dev_pm_ops brcm_pcie_pm_ops = {
+     .suspend_noirq = brcm_pcie_suspend,
+     .resume_noirq = brcm_pcie_resume,

Why do you need interrupts disabled? There's 39 cases of .suspend_noirq
and 1352 of .suspend in the tree.

I will test switching this to  suspend_late/resume_early.

Thanks,
Jim Quinlan
Broadcom STB

Is doing a clk unprepare even safe in .suspend_noirq? IIRC,
prepare/unprepare can sleep.

quoted

+};
+
 static struct platform_driver brcm_pcie_driver = {
      .probe = brcm_pcie_probe,
      .remove = brcm_pcie_remove,
      .driver = {
              .name = "brcm-pcie",
              .of_match_table = brcm_pcie_match,
+             .pm = &brcm_pcie_pm_ops,
      },
 };
 module_platform_driver(brcm_pcie_driver);
--
2.17.1