From: Kazufumi Ikeda <kaz-ikeda@xxxxxxxxxxxxx>
Reestablish the PCIe link very early in the resume process in case it
went down to prevent PCI accesses from hanging the bus. Such accesses
can happen early in the PCI resume process, as early as the
SUSPEND_RESUME_NOIRQ step, thus the link must be reestablished in the
driver resume_noirq() callback.
Fixes: e015f88c368d ("PCI: rcar: Add support for R-Car H3 to pcie-rcar")
Signed-off-by: Kazufumi Ikeda <kaz-ikeda@xxxxxxxxxxxxx>
Signed-off-by: Gaku Inami <gaku.inami.xw@xxxxxxxxxxxxxx>
Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxx>
[lorenzo.pieralisi@xxxxxxx: reformatted commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Reviewed-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
Acked-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Cc: Phil Edworthy <phil.edworthy@xxxxxxxxxxx>
Cc: Simon Horman <horms+renesas@xxxxxxxxxxxx>
Cc: Wolfram Sang <wsa@xxxxxxxxxxxxx>
Cc: linux-renesas-soc@xxxxxxxxxxxxxxx
---
V2: - Use BIT() macro for (1 << n)
- Since polling in rcar_pcie_wait_for_dl() uses udelay(), do not
add extra changes to this function anymore
- Make resume_noirq return early and clean up parenthesis therein
V3: - Add missing PMSR register definition, dropped due to patch reshuffling
---
drivers/pci/controller/pcie-rcar.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c
index c8febb009454..6a4e435bd35f 100644
--- a/drivers/pci/controller/pcie-rcar.c
+++ b/drivers/pci/controller/pcie-rcar.c
@@ -46,6 +46,7 @@
/* Transfer control */
#define PCIETCTLR 0x02000
+#define DL_DOWN BIT(3)
#define CFINIT 1
#define PCIETSTR 0x02004
#define DATA_LINK_ACTIVE 1
@@ -94,6 +95,7 @@
#define MACCTLR 0x011058
#define SPEED_CHANGE BIT(24)
#define SCRAMBLE_DISABLE BIT(27)
+#define PMSR 0x01105c
#define MACS2R 0x011078
#define MACCGSPSETR 0x011084
#define SPCNGRSN BIT(31)
@@ -1130,6 +1132,7 @@ static int rcar_pcie_probe(struct platform_device *pdev)
pcie = pci_host_bridge_priv(bridge);
pcie->dev = dev;
+ platform_set_drvdata(pdev, pcie);
err = pci_parse_request_of_pci_ranges(dev, &pcie->resources, NULL);
if (err)
@@ -1221,10 +1224,28 @@ static int rcar_pcie_probe(struct platform_device *pdev)
return err;
}
+static int rcar_pcie_resume_noirq(struct device *dev)
+{
+ struct rcar_pcie *pcie = dev_get_drvdata(dev);
+
+ if (rcar_pci_read_reg(pcie, PMSR) &&
+ !(rcar_pci_read_reg(pcie, PCIETCTLR) & DL_DOWN))
+ return 0;
+
+ /* Re-establish the PCIe link */
+ rcar_pci_write_reg(pcie, CFINIT, PCIETCTLR);
+ return rcar_pcie_wait_for_dl(pcie);
+}
+
+static const struct dev_pm_ops rcar_pcie_pm_ops = {
+ .resume_noirq = rcar_pcie_resume_noirq,
+};
+
static struct platform_driver rcar_pcie_driver = {
.driver = {
.name = "rcar-pcie",
.of_match_table = rcar_pcie_of_match,
+ .pm = &rcar_pcie_pm_ops,
.suppress_bind_attrs = true,
},
.probe = rcar_pcie_probe,
--
2.20.1
