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 <[email protected]>
Signed-off-by: Krzysztof Wilczyński <[email protected]>
Link: https://patch.msgid.link/[email protected]

1 files changed, 248 insertions, 0 deletions

diff --git a/drivers/pci/controller/dwc/pcie-designware-debugfs.c b/drivers/pci/controller/dwc/pcie-designware-debugfs.c
index 896c387450ca..c67601096c48 100644
--- 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);
 }