PCI: dwc: Add debugfs support for PTM context

Synopsys Designware PCIe IPs support PTM capability as defined in the PCIe
spec r6.0, sec 6.21. The PTM context information is exposed through Vendor
Specific Extended Capability (VSEC) registers on supported controller
implementation.

Hence, add support for exposing these context information to userspace
through the debugfs interface for the DWC controllers (both RC and EP).
Currently, only Qcom controllers are supported. For adding support for
other DWC vendor controllers, dwc_pcie_ptm_vsec_ids[] needs to be extended.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Link: https://patch.msgid.link/20250505-pcie-ptm-v4-3-02d26d51400b@linaro.org

diff --git a/drivers/pci/controller/dwc/pcie-designware-debugfs.c b/drivers/pci/controller/dwc/pcie-designware-debugfs.c
index 896c387450ca45d979f6baa04e6b3ae3e4be167e..c67601096c4827b144d624dbaf18091eea2a0d5b 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware-debugfs.c
+++ b/drivers/pci/controller/dwc/pcie-designware-debugfs.c
@@ -642,11 +642,257 @@ static void dwc_pcie_ltssm_debugfs_init(struct dw_pcie *pci, struct dentry *dir)
                            &dwc_pcie_ltssm_status_ops);
 }
 
+static int dw_pcie_ptm_check_capability(void *drvdata)
+{
+       struct dw_pcie *pci = drvdata;
+
+       pci->ptm_vsec_offset = dw_pcie_find_ptm_capability(pci);
+
+       return pci->ptm_vsec_offset;
+}
+
+static int dw_pcie_ptm_context_update_write(void *drvdata, u8 mode)
+{
+       struct dw_pcie *pci = drvdata;
+       u32 val;
+
+       if (mode == PCIE_PTM_CONTEXT_UPDATE_AUTO) {
+               val = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_RES_REQ_CTRL);
+               val |= PTM_REQ_AUTO_UPDATE_ENABLED;
+               dw_pcie_writel_dbi(pci, pci->ptm_vsec_offset + PTM_RES_REQ_CTRL, val);
+       } else if (mode == PCIE_PTM_CONTEXT_UPDATE_MANUAL) {
+               val = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_RES_REQ_CTRL);
+               val &= ~PTM_REQ_AUTO_UPDATE_ENABLED;
+               val |= PTM_REQ_START_UPDATE;
+               dw_pcie_writel_dbi(pci, pci->ptm_vsec_offset + PTM_RES_REQ_CTRL, val);
+       } else {
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static int dw_pcie_ptm_context_update_read(void *drvdata, u8 *mode)
+{
+       struct dw_pcie *pci = drvdata;
+       u32 val;
+
+       val = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_RES_REQ_CTRL);
+       if (FIELD_GET(PTM_REQ_AUTO_UPDATE_ENABLED, val))
+               *mode = PCIE_PTM_CONTEXT_UPDATE_AUTO;
+       else
+               /*
+                * PTM_REQ_START_UPDATE is a self clearing register bit. So if
+                * PTM_REQ_AUTO_UPDATE_ENABLED is not set, then it implies that
+                * manual update is used.
+                */
+               *mode = PCIE_PTM_CONTEXT_UPDATE_MANUAL;
+
+       return 0;
+}
+
+static int dw_pcie_ptm_context_valid_write(void *drvdata, bool valid)
+{
+       struct dw_pcie *pci = drvdata;
+       u32 val;
+
+       if (valid) {
+               val = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_RES_REQ_CTRL);
+               val |= PTM_RES_CCONTEXT_VALID;
+               dw_pcie_writel_dbi(pci, pci->ptm_vsec_offset + PTM_RES_REQ_CTRL, val);
+       } else {
+               val = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_RES_REQ_CTRL);
+               val &= ~PTM_RES_CCONTEXT_VALID;
+               dw_pcie_writel_dbi(pci, pci->ptm_vsec_offset + PTM_RES_REQ_CTRL, val);
+       }
+
+       return 0;
+}
+
+static int dw_pcie_ptm_context_valid_read(void *drvdata, bool *valid)
+{
+       struct dw_pcie *pci = drvdata;
+       u32 val;
+
+       val = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_RES_REQ_CTRL);
+       *valid = !!FIELD_GET(PTM_RES_CCONTEXT_VALID, val);
+
+       return 0;
+}
+
+static int dw_pcie_ptm_local_clock_read(void *drvdata, u64 *clock)
+{
+       struct dw_pcie *pci = drvdata;
+       u32 msb, lsb;
+
+       do {
+               msb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_LOCAL_MSB);
+               lsb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_LOCAL_LSB);
+       } while (msb != dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_LOCAL_MSB));
+
+       *clock = ((u64) msb) << 32 | lsb;
+
+       return 0;
+}
+
+static int dw_pcie_ptm_master_clock_read(void *drvdata, u64 *clock)
+{
+       struct dw_pcie *pci = drvdata;
+       u32 msb, lsb;
+
+       do {
+               msb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_MASTER_MSB);
+               lsb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_MASTER_LSB);
+       } while (msb != dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_MASTER_MSB));
+
+       *clock = ((u64) msb) << 32 | lsb;
+
+       return 0;
+}
+
+static int dw_pcie_ptm_t1_read(void *drvdata, u64 *clock)
+{
+       struct dw_pcie *pci = drvdata;
+       u32 msb, lsb;
+
+       do {
+               msb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T1_T2_MSB);
+               lsb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T1_T2_LSB);
+       } while (msb != dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T1_T2_MSB));
+
+       *clock = ((u64) msb) << 32 | lsb;
+
+       return 0;
+}
+
+static int dw_pcie_ptm_t2_read(void *drvdata, u64 *clock)
+{
+       struct dw_pcie *pci = drvdata;
+       u32 msb, lsb;
+
+       do {
+               msb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T1_T2_MSB);
+               lsb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T1_T2_LSB);
+       } while (msb != dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T1_T2_MSB));
+
+       *clock = ((u64) msb) << 32 | lsb;
+
+       return 0;
+}
+
+static int dw_pcie_ptm_t3_read(void *drvdata, u64 *clock)
+{
+       struct dw_pcie *pci = drvdata;
+       u32 msb, lsb;
+
+       do {
+               msb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T3_T4_MSB);
+               lsb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T3_T4_LSB);
+       } while (msb != dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T3_T4_MSB));
+
+       *clock = ((u64) msb) << 32 | lsb;
+
+       return 0;
+}
+
+static int dw_pcie_ptm_t4_read(void *drvdata, u64 *clock)
+{
+       struct dw_pcie *pci = drvdata;
+       u32 msb, lsb;
+
+       do {
+               msb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T3_T4_MSB);
+               lsb = dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T3_T4_LSB);
+       } while (msb != dw_pcie_readl_dbi(pci, pci->ptm_vsec_offset + PTM_T3_T4_MSB));
+
+       *clock = ((u64) msb) << 32 | lsb;
+
+       return 0;
+}
+
+static bool dw_pcie_ptm_context_update_visible(void *drvdata)
+{
+       struct dw_pcie *pci = drvdata;
+
+       return (pci->mode == DW_PCIE_EP_TYPE) ? true : false;
+}
+
+static bool dw_pcie_ptm_context_valid_visible(void *drvdata)
+{
+       struct dw_pcie *pci = drvdata;
+
+       return (pci->mode == DW_PCIE_RC_TYPE) ? true : false;
+}
+
+static bool dw_pcie_ptm_local_clock_visible(void *drvdata)
+{
+       /* PTM local clock is always visible */
+       return true;
+}
+
+static bool dw_pcie_ptm_master_clock_visible(void *drvdata)
+{
+       struct dw_pcie *pci = drvdata;
+
+       return (pci->mode == DW_PCIE_EP_TYPE) ? true : false;
+}
+
+static bool dw_pcie_ptm_t1_visible(void *drvdata)
+{
+       struct dw_pcie *pci = drvdata;
+
+       return (pci->mode == DW_PCIE_EP_TYPE) ? true : false;
+}
+
+static bool dw_pcie_ptm_t2_visible(void *drvdata)
+{
+       struct dw_pcie *pci = drvdata;
+
+       return (pci->mode == DW_PCIE_RC_TYPE) ? true : false;
+}
+
+static bool dw_pcie_ptm_t3_visible(void *drvdata)
+{
+       struct dw_pcie *pci = drvdata;
+
+       return (pci->mode == DW_PCIE_RC_TYPE) ? true : false;
+}
+
+static bool dw_pcie_ptm_t4_visible(void *drvdata)
+{
+       struct dw_pcie *pci = drvdata;
+
+       return (pci->mode == DW_PCIE_EP_TYPE) ? true : false;
+}
+
+const struct pcie_ptm_ops dw_pcie_ptm_ops = {
+       .check_capability = dw_pcie_ptm_check_capability,
+       .context_update_write = dw_pcie_ptm_context_update_write,
+       .context_update_read = dw_pcie_ptm_context_update_read,
+       .context_valid_write = dw_pcie_ptm_context_valid_write,
+       .context_valid_read = dw_pcie_ptm_context_valid_read,
+       .local_clock_read = dw_pcie_ptm_local_clock_read,
+       .master_clock_read = dw_pcie_ptm_master_clock_read,
+       .t1_read = dw_pcie_ptm_t1_read,
+       .t2_read = dw_pcie_ptm_t2_read,
+       .t3_read = dw_pcie_ptm_t3_read,
+       .t4_read = dw_pcie_ptm_t4_read,
+       .context_update_visible = dw_pcie_ptm_context_update_visible,
+       .context_valid_visible = dw_pcie_ptm_context_valid_visible,
+       .local_clock_visible = dw_pcie_ptm_local_clock_visible,
+       .master_clock_visible = dw_pcie_ptm_master_clock_visible,
+       .t1_visible = dw_pcie_ptm_t1_visible,
+       .t2_visible = dw_pcie_ptm_t2_visible,
+       .t3_visible = dw_pcie_ptm_t3_visible,
+       .t4_visible = dw_pcie_ptm_t4_visible,
+};
+
 void dwc_pcie_debugfs_deinit(struct dw_pcie *pci)
 {
        if (!pci->debugfs)
                return;
 
+       pcie_ptm_destroy_debugfs(pci->ptm_debugfs);
        dwc_pcie_rasdes_debugfs_deinit(pci);
        debugfs_remove_recursive(pci->debugfs->debug_dir);
 }
@@ -676,4 +922,6 @@ void dwc_pcie_debugfs_init(struct dw_pcie *pci, enum dw_pcie_device_mode mode)
        dwc_pcie_ltssm_debugfs_init(pci, dir);
 
        pci->mode = mode;
+       pci->ptm_debugfs = pcie_ptm_create_debugfs(pci->dev, pci,
+                                                  &dw_pcie_ptm_ops);
 }

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 97d76d3dc066efeff093de28dcac64411dad51aa..4a9b1ebda67993104233c48eea217d36da42f353 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -54,6 +54,14 @@ static const char * const dw_pcie_core_rsts[DW_PCIE_NUM_CORE_RSTS] = {
        [DW_PCIE_PWR_RST] = "pwr",
 };
 
+static const struct dwc_pcie_vsec_id dwc_pcie_ptm_vsec_ids[] = {
+       { .vendor_id = PCI_VENDOR_ID_QCOM, /* EP */
+         .vsec_id = 0x03, .vsec_rev = 0x1 },
+       { .vendor_id = PCI_VENDOR_ID_QCOM, /* RC */
+         .vsec_id = 0x04, .vsec_rev = 0x1 },
+       { }
+};
+
 static int dw_pcie_get_clocks(struct dw_pcie *pci)
 {
        int i, ret;
@@ -330,6 +338,12 @@ u16 dw_pcie_find_rasdes_capability(struct dw_pcie *pci)
 }
 EXPORT_SYMBOL_GPL(dw_pcie_find_rasdes_capability);
 
+u16 dw_pcie_find_ptm_capability(struct dw_pcie *pci)
+{
+       return dw_pcie_find_vsec_capability(pci, dwc_pcie_ptm_vsec_ids);
+}
+EXPORT_SYMBOL_GPL(dw_pcie_find_ptm_capability);
+
 int dw_pcie_read(void __iomem *addr, int size, u32 *val)
 {
        if (!IS_ALIGNED((uintptr_t)addr, size)) {

diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 7f58c94b5b1e9a590692474d5efa80c5b5ed9b8d..4d41274a69379f2c563e509df6a8c169c17f9f3c 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -260,6 +260,21 @@
 
 #define PCIE_RAS_DES_EVENT_COUNTER_DATA                0xc
 
+/* PTM register definitions */
+#define PTM_RES_REQ_CTRL               0x8
+#define PTM_RES_CCONTEXT_VALID         BIT(0)
+#define PTM_REQ_AUTO_UPDATE_ENABLED    BIT(0)
+#define PTM_REQ_START_UPDATE           BIT(1)
+
+#define PTM_LOCAL_LSB                  0x10
+#define PTM_LOCAL_MSB                  0x14
+#define PTM_T1_T2_LSB                  0x18
+#define PTM_T1_T2_MSB                  0x1c
+#define PTM_T3_T4_LSB                  0x28
+#define PTM_T3_T4_MSB                  0x2c
+#define PTM_MASTER_LSB                 0x38
+#define PTM_MASTER_MSB                 0x3c
+
 /*
  * The default address offset between dbi_base and atu_base. Root controller
  * drivers are not required to initialize atu_base if the offset matches this
@@ -504,6 +519,8 @@ struct dw_pcie {
        bool                    suspended;
        struct debugfs_info     *debugfs;
        enum                    dw_pcie_device_mode mode;
+       u16                     ptm_vsec_offset;
+       struct pci_ptm_debugfs  *ptm_debugfs;
 
        /*
         * If iATU input addresses are offset from CPU physical addresses,
@@ -531,6 +548,7 @@ void dw_pcie_version_detect(struct dw_pcie *pci);
 u8 dw_pcie_find_capability(struct dw_pcie *pci, u8 cap);
 u16 dw_pcie_find_ext_capability(struct dw_pcie *pci, u8 cap);
 u16 dw_pcie_find_rasdes_capability(struct dw_pcie *pci);
+u16 dw_pcie_find_ptm_capability(struct dw_pcie *pci);
 
 int dw_pcie_read(void __iomem *addr, int size, u32 *val);
 int dw_pcie_write(void __iomem *addr, int size, u32 val);