Merge branch 'remotes/lorenzo/pci/iproc'

  - Work around iproc CRS completion issues (Srinath Mannam)

  - Allow smaller iproc outbound windows so driver can work on 32-bit
    systems (Srinath Mannam)

  - Use iproc-specific config read for PAXBv2 (not PAXB) (Srinath Mannam)

* remotes/lorenzo/pci/iproc:
  PCI: iproc: Enable iProc config read for PAXBv2
  PCI: iproc: Allow outbound configuration for 32-bit I/O region
  PCI: iproc: Add CRS check in config read

1 files changed, 41 insertions, 5 deletions

diff --git a/drivers/pci/controller/pcie-iproc.c b/drivers/pci/controller/pcie-iproc.c
index c20fd6bd68fd..dd11d0226ff0 100644
--- a/drivers/pci/controller/pcie-iproc.c
+++ b/drivers/pci/controller/pcie-iproc.c
@@ -60,6 +60,10 @@
 #define APB_ERR_EN_SHIFT		0
 #define APB_ERR_EN			BIT(APB_ERR_EN_SHIFT)
 
+#define CFG_RD_SUCCESS			0
+#define CFG_RD_UR			1
+#define CFG_RD_CRS			2
+#define CFG_RD_CA			3
 #define CFG_RETRY_STATUS		0xffff0001
 #define CFG_RETRY_STATUS_TIMEOUT_US	500000 /* 500 milliseconds */
 
@@ -289,6 +293,9 @@ enum iproc_pcie_reg {
 	IPROC_PCIE_IARR4,
 	IPROC_PCIE_IMAP4,
 
+	/* config read status */
+	IPROC_PCIE_CFG_RD_STATUS,
+
 	/* link status */
 	IPROC_PCIE_LINK_STATUS,
 
@@ -350,6 +357,7 @@ static const u16 iproc_pcie_reg_paxb_v2[] = {
 	[IPROC_PCIE_IMAP3]		= 0xe08,
 	[IPROC_PCIE_IARR4]		= 0xe68,
 	[IPROC_PCIE_IMAP4]		= 0xe70,
+	[IPROC_PCIE_CFG_RD_STATUS]	= 0xee0,
 	[IPROC_PCIE_LINK_STATUS]	= 0xf0c,
 	[IPROC_PCIE_APB_ERR_EN]		= 0xf40,
 };
@@ -474,10 +482,12 @@ static void __iomem *iproc_pcie_map_ep_cfg_reg(struct iproc_pcie *pcie,
 	return (pcie->base + offset);
 }
 
-static unsigned int iproc_pcie_cfg_retry(void __iomem *cfg_data_p)
+static unsigned int iproc_pcie_cfg_retry(struct iproc_pcie *pcie,
+					 void __iomem *cfg_data_p)
 {
 	int timeout = CFG_RETRY_STATUS_TIMEOUT_US;
 	unsigned int data;
+	u32 status;
 
 	/*
 	 * As per PCIe spec r3.1, sec 2.3.2, CRS Software Visibility only
@@ -498,6 +508,15 @@ static unsigned int iproc_pcie_cfg_retry(void __iomem *cfg_data_p)
 	 */
 	data = readl(cfg_data_p);
 	while (data == CFG_RETRY_STATUS && timeout--) {
+		/*
+		 * CRS state is set in CFG_RD status register
+		 * This will handle the case where CFG_RETRY_STATUS is
+		 * valid config data.
+		 */
+		status = iproc_pcie_read_reg(pcie, IPROC_PCIE_CFG_RD_STATUS);
+		if (status != CFG_RD_CRS)
+			return data;
+
 		udelay(1);
 		data = readl(cfg_data_p);
 	}
@@ -576,7 +595,7 @@ static int iproc_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
 	if (!cfg_data_p)
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
-	data = iproc_pcie_cfg_retry(cfg_data_p);
+	data = iproc_pcie_cfg_retry(pcie, cfg_data_p);
 
 	*val = data;
 	if (size <= 2)
@@ -936,8 +955,25 @@ static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
 			resource_size_t window_size =
 				ob_map->window_sizes[size_idx] * SZ_1M;
 
-			if (size < window_size)
-				continue;
+			/*
+			 * Keep iterating until we reach the last window and
+			 * with the minimal window size at index zero. In this
+			 * case, we take a compromise by mapping it using the
+			 * minimum window size that can be supported
+			 */
+			if (size < window_size) {
+				if (size_idx > 0 || window_idx > 0)
+					continue;
+
+				/*
+				 * For the corner case of reaching the minimal
+				 * window size that can be supported on the
+				 * last window
+				 */
+				axi_addr = ALIGN_DOWN(axi_addr, window_size);
+				pci_addr = ALIGN_DOWN(pci_addr, window_size);
+				size = window_size;
+			}
 
 			if (!IS_ALIGNED(axi_addr, window_size) ||
 			    !IS_ALIGNED(pci_addr, window_size)) {
@@ -1347,7 +1383,6 @@ static int iproc_pcie_rev_init(struct iproc_pcie *pcie)
 		break;
 	case IPROC_PCIE_PAXB:
 		regs = iproc_pcie_reg_paxb;
-		pcie->iproc_cfg_read = true;
 		pcie->has_apb_err_disable = true;
 		if (pcie->need_ob_cfg) {
 			pcie->ob_map = paxb_ob_map;
@@ -1356,6 +1391,7 @@ static int iproc_pcie_rev_init(struct iproc_pcie *pcie)
 		break;
 	case IPROC_PCIE_PAXB_V2:
 		regs = iproc_pcie_reg_paxb_v2;
+		pcie->iproc_cfg_read = true;
 		pcie->has_apb_err_disable = true;
 		if (pcie->need_ob_cfg) {
 			pcie->ob_map = paxb_v2_ob_map;