PCI: tegra194: Find RAS DES PCIe capability offset

Find RAS DES PCIe capability offset instead of hardcoding the offset
for each controller.

Link: https://lore.kernel.org/r/20220721142052.25971-10-vidyas@nvidia.com
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Author: Vidya Sagar

drivers/pci/controller/dwc/pcie-designware.h

@@ -130,6 +130,25 @@
 #define PCIE_ATU_UNR_UPPER_TARGET	0x18
 #define PCIE_ATU_UNR_UPPER_LIMIT	0x20
 
+/*
+ * RAS-DES register definitions
+ */
+#define PCIE_RAS_DES_EVENT_COUNTER_CONTROL	0x8
+#define EVENT_COUNTER_ALL_CLEAR		0x3
+#define EVENT_COUNTER_ENABLE_ALL	0x7
+#define EVENT_COUNTER_ENABLE_SHIFT	2
+#define EVENT_COUNTER_EVENT_SEL_MASK	GENMASK(7, 0)
+#define EVENT_COUNTER_EVENT_SEL_SHIFT	16
+#define EVENT_COUNTER_EVENT_Tx_L0S	0x2
+#define EVENT_COUNTER_EVENT_Rx_L0S	0x3
+#define EVENT_COUNTER_EVENT_L1		0x5
+#define EVENT_COUNTER_EVENT_L1_1	0x7
+#define EVENT_COUNTER_EVENT_L1_2	0x8
+#define EVENT_COUNTER_GROUP_SEL_SHIFT	24
+#define EVENT_COUNTER_GROUP_5		0x5
+
+#define PCIE_RAS_DES_EVENT_COUNTER_DATA		0xc
+
 /*
  * 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

drivers/pci/controller/dwc/pcie-tegra194.c

@@ -170,19 +170,6 @@
 #define CFG_TIMER_CTRL_MAX_FUNC_NUM_OFF	0x718
 #define CFG_TIMER_CTRL_ACK_NAK_SHIFT	(19)
 
-#define EVENT_COUNTER_ALL_CLEAR		0x3
-#define EVENT_COUNTER_ENABLE_ALL	0x7
-#define EVENT_COUNTER_ENABLE_SHIFT	2
-#define EVENT_COUNTER_EVENT_SEL_MASK	GENMASK(7, 0)
-#define EVENT_COUNTER_EVENT_SEL_SHIFT	16
-#define EVENT_COUNTER_EVENT_Tx_L0S	0x2
-#define EVENT_COUNTER_EVENT_Rx_L0S	0x3
-#define EVENT_COUNTER_EVENT_L1		0x5
-#define EVENT_COUNTER_EVENT_L1_1	0x7
-#define EVENT_COUNTER_EVENT_L1_2	0x8
-#define EVENT_COUNTER_GROUP_SEL_SHIFT	24
-#define EVENT_COUNTER_GROUP_5		0x5
-
 #define N_FTS_VAL					52
 #define FTS_VAL						52
 
@@ -266,6 +253,7 @@ struct tegra_pcie_dw {
 	u32 num_lanes;
 	u32 cid;
 	u32 cfg_link_cap_l1sub;
+	u32 ras_des_cap;
 	u32 pcie_cap_base;
 	u32 aspm_cmrt;
 	u32 aspm_pwr_on_t;
@@ -574,24 +562,6 @@ static struct pci_ops tegra_pci_ops = {
 };
 
 #if defined(CONFIG_PCIEASPM)
-static const u32 event_cntr_ctrl_offset[] = {
-	0x1d8,
-	0x1a8,
-	0x1a8,
-	0x1a8,
-	0x1c4,
-	0x1d8
-};
-
-static const u32 event_cntr_data_offset[] = {
-	0x1dc,
-	0x1ac,
-	0x1ac,
-	0x1ac,
-	0x1c8,
-	0x1dc
-};
-
 static void disable_aspm_l11(struct tegra_pcie_dw *pcie)
 {
 	u32 val;
@@ -614,13 +584,16 @@ static inline u32 event_counter_prog(struct tegra_pcie_dw *pcie, u32 event)
 {
 	u32 val;
 
-	val = dw_pcie_readl_dbi(&pcie->pci, event_cntr_ctrl_offset[pcie->cid]);
+	val = dw_pcie_readl_dbi(&pcie->pci, pcie->ras_des_cap +
+				PCIE_RAS_DES_EVENT_COUNTER_CONTROL);
 	val &= ~(EVENT_COUNTER_EVENT_SEL_MASK << EVENT_COUNTER_EVENT_SEL_SHIFT);
 	val |= EVENT_COUNTER_GROUP_5 << EVENT_COUNTER_GROUP_SEL_SHIFT;
 	val |= event << EVENT_COUNTER_EVENT_SEL_SHIFT;
 	val |= EVENT_COUNTER_ENABLE_ALL << EVENT_COUNTER_ENABLE_SHIFT;
-	dw_pcie_writel_dbi(&pcie->pci, event_cntr_ctrl_offset[pcie->cid], val);
-	val = dw_pcie_readl_dbi(&pcie->pci, event_cntr_data_offset[pcie->cid]);
+	dw_pcie_writel_dbi(&pcie->pci, pcie->ras_des_cap +
+			   PCIE_RAS_DES_EVENT_COUNTER_CONTROL, val);
+	val = dw_pcie_readl_dbi(&pcie->pci, pcie->ras_des_cap +
+				PCIE_RAS_DES_EVENT_COUNTER_DATA);
 
 	return val;
 }
@@ -647,13 +620,15 @@ static int aspm_state_cnt(struct seq_file *s, void *data)
 		   event_counter_prog(pcie, EVENT_COUNTER_EVENT_L1_2));
 
 	/* Clear all counters */
-	dw_pcie_writel_dbi(&pcie->pci, event_cntr_ctrl_offset[pcie->cid],
+	dw_pcie_writel_dbi(&pcie->pci, pcie->ras_des_cap +
+			   PCIE_RAS_DES_EVENT_COUNTER_CONTROL,
 			   EVENT_COUNTER_ALL_CLEAR);
 
 	/* Re-enable counting */
 	val = EVENT_COUNTER_ENABLE_ALL << EVENT_COUNTER_ENABLE_SHIFT;
 	val |= EVENT_COUNTER_GROUP_5 << EVENT_COUNTER_GROUP_SEL_SHIFT;
-	dw_pcie_writel_dbi(&pcie->pci, event_cntr_ctrl_offset[pcie->cid], val);
+	dw_pcie_writel_dbi(&pcie->pci, pcie->ras_des_cap +
+			   PCIE_RAS_DES_EVENT_COUNTER_CONTROL, val);
 
 	return 0;
 }
@@ -666,10 +641,14 @@ static void init_host_aspm(struct tegra_pcie_dw *pcie)
 	val = dw_pcie_find_ext_capability(pci, PCI_EXT_CAP_ID_L1SS);
 	pcie->cfg_link_cap_l1sub = val + PCI_L1SS_CAP;
 
+	pcie->ras_des_cap = dw_pcie_find_ext_capability(&pcie->pci,
+							PCI_EXT_CAP_ID_VNDR);
+
 	/* Enable ASPM counters */
 	val = EVENT_COUNTER_ENABLE_ALL << EVENT_COUNTER_ENABLE_SHIFT;
 	val |= EVENT_COUNTER_GROUP_5 << EVENT_COUNTER_GROUP_SEL_SHIFT;
-	dw_pcie_writel_dbi(pci, event_cntr_ctrl_offset[pcie->cid], val);
+	dw_pcie_writel_dbi(pci, pcie->ras_des_cap +
+			   PCIE_RAS_DES_EVENT_COUNTER_CONTROL, val);
 
 	/* Program T_cmrt and T_pwr_on values */
 	val = dw_pcie_readl_dbi(pci, pcie->cfg_link_cap_l1sub);