[PATCH v2 3/3] PCI: layerscape: Add suspend/resume for ls1043a

From: Frank Li
Date: Mon Oct 16 2023 - 12:20:22 EST


ls1043a add suspend/resume support.

Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---

Notes:
Change from v1 to v2
- Change subject 'a' to 'A'

drivers/pci/controller/dwc/pci-layerscape.c | 91 ++++++++++++++++++++-
1 file changed, 90 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pci-layerscape.c b/drivers/pci/controller/dwc/pci-layerscape.c
index bc5a8ff1a26c..debabb9bb41f 100644
--- a/drivers/pci/controller/dwc/pci-layerscape.c
+++ b/drivers/pci/controller/dwc/pci-layerscape.c
@@ -41,10 +41,20 @@
#define SCFG_PEXSFTRSTCR 0x190
#define PEXSR(idx) BIT(idx)

+/* LS1043A PEX PME control register */
+#define SCFG_PEXPMECR 0x144
+#define PEXPME(idx) BIT(31 - (idx) * 4)
+
+/* LS1043A PEX LUT debug register */
+#define LS_PCIE_LDBG 0x7fc
+#define LDBG_SR BIT(30)
+#define LDBG_WE BIT(31)
+
#define PCIE_IATU_NUM 6

struct ls_pcie_drvdata {
const u32 pf_off;
+ const u32 lut_off;
const struct dw_pcie_host_ops *ops;
void (*exit_from_l2)(struct dw_pcie_rp *pp);
bool pm_support;
@@ -54,6 +64,7 @@ struct ls_pcie {
struct dw_pcie *pci;
const struct ls_pcie_drvdata *drvdata;
void __iomem *pf_base;
+ void __iomem *lut_base;
struct regmap *scfg;
int index;
bool big_endian;
@@ -116,6 +127,23 @@ static void ls_pcie_pf_writel(struct ls_pcie *pcie, u32 off, u32 val)
iowrite32(val, pcie->pf_base + off);
}

+static u32 ls_pcie_lut_readl(struct ls_pcie *pcie, u32 off)
+{
+ if (pcie->big_endian)
+ return ioread32be(pcie->lut_base + off);
+
+ return ioread32(pcie->lut_base + off);
+}
+
+static void ls_pcie_lut_writel(struct ls_pcie *pcie, u32 off, u32 val)
+{
+ if (pcie->big_endian)
+ iowrite32be(val, pcie->lut_base + off);
+ else
+ iowrite32(val, pcie->lut_base + off);
+}
+
+
static void ls_pcie_send_turnoff_msg(struct dw_pcie_rp *pp)
{
struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
@@ -249,6 +277,54 @@ static int ls1021a_pcie_host_init(struct dw_pcie_rp *pp)
return ret;
}

+static void ls1043a_pcie_send_turnoff_msg(struct dw_pcie_rp *pp)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+ struct ls_pcie *pcie = to_ls_pcie(pci);
+ u32 val;
+
+ if (!pcie->scfg) {
+ dev_dbg(pcie->pci->dev, "SYSCFG is NULL\n");
+ return;
+ }
+
+ /* Send Turn_off message */
+ regmap_read(pcie->scfg, SCFG_PEXPMECR, &val);
+ val |= PEXPME(pcie->index);
+ regmap_write(pcie->scfg, SCFG_PEXPMECR, val);
+
+ /* There are not register to check ACK, so wait PCIE_PME_TO_L2_TIMEOUT_US */
+ mdelay(PCIE_PME_TO_L2_TIMEOUT_US/1000);
+
+ /* Clear Turn_off message */
+ regmap_read(pcie->scfg, SCFG_PEXPMECR, &val);
+ val &= ~PEXPME(pcie->index);
+ regmap_write(pcie->scfg, SCFG_PEXPMECR, val);
+}
+
+static void ls1043a_pcie_exit_from_l2(struct dw_pcie_rp *pp)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+ struct ls_pcie *pcie = to_ls_pcie(pci);
+ u32 val;
+
+ val = ls_pcie_lut_readl(pcie, LS_PCIE_LDBG);
+ val |= LDBG_WE;
+ ls_pcie_lut_writel(pcie, LS_PCIE_LDBG, val);
+
+ val = ls_pcie_lut_readl(pcie, LS_PCIE_LDBG);
+ val |= LDBG_SR;
+ ls_pcie_lut_writel(pcie, LS_PCIE_LDBG, val);
+
+ val = ls_pcie_lut_readl(pcie, LS_PCIE_LDBG);
+ val &= ~LDBG_SR;
+ ls_pcie_lut_writel(pcie, LS_PCIE_LDBG, val);
+
+ val = ls_pcie_lut_readl(pcie, LS_PCIE_LDBG);
+ val &= ~LDBG_WE;
+ ls_pcie_lut_writel(pcie, LS_PCIE_LDBG, val);
+}
+
static const struct dw_pcie_host_ops ls_pcie_host_ops = {
.host_init = ls_pcie_host_init,
.pme_turn_off = ls_pcie_send_turnoff_msg,
@@ -265,6 +341,18 @@ static const struct ls_pcie_drvdata ls1021a_drvdata = {
.exit_from_l2 = ls1021a_pcie_exit_from_l2,
};

+static const struct dw_pcie_host_ops ls1043a_pcie_host_ops = {
+ .host_init = ls1021a_pcie_host_init, /* the same as ls1021 */
+ .pme_turn_off = ls1043a_pcie_send_turnoff_msg,
+};
+
+static const struct ls_pcie_drvdata ls1043a_drvdata = {
+ .lut_off = 0x10000,
+ .pm_support = true,
+ .ops = &ls1043a_pcie_host_ops,
+ .exit_from_l2 = ls1043a_pcie_exit_from_l2,
+};
+
static const struct ls_pcie_drvdata layerscape_drvdata = {
.pf_off = 0xc0000,
.pm_support = true,
@@ -275,7 +363,7 @@ static const struct of_device_id ls_pcie_of_match[] = {
{ .compatible = "fsl,ls1012a-pcie", .data = &layerscape_drvdata },
{ .compatible = "fsl,ls1021a-pcie", .data = &ls1021a_drvdata },
{ .compatible = "fsl,ls1028a-pcie", .data = &layerscape_drvdata },
- { .compatible = "fsl,ls1043a-pcie", .data = &ls1021a_drvdata },
+ { .compatible = "fsl,ls1043a-pcie", .data = &ls1043a_drvdata },
{ .compatible = "fsl,ls1046a-pcie", .data = &layerscape_drvdata },
{ .compatible = "fsl,ls2080a-pcie", .data = &layerscape_drvdata },
{ .compatible = "fsl,ls2085a-pcie", .data = &layerscape_drvdata },
@@ -314,6 +402,7 @@ static int ls_pcie_probe(struct platform_device *pdev)
pcie->big_endian = of_property_read_bool(dev->of_node, "big-endian");

pcie->pf_base = pci->dbi_base + pcie->drvdata->pf_off;
+ pcie->lut_base = pci->dbi_base + pcie->drvdata->lut_off;

if (!ls_pcie_is_bridge(pcie))
return -ENODEV;
--
2.34.1