[PATCH 8/8] PCI: rockchip: Fixed MSI generation from PCIe endpoint core

[Rick Wertenbroek]

The generation of MSI interrupts from the RK3399 PCIe endpoint core was
broken. The main issue came from u16 variables to be used to access u32
registers, this would lead to shifts of more than 16 bits moving data
out of the variable etc. Address translation for sending the MSI messages
over PCIe has also been fixed.

Signed-off-by: Rick Wertenbroek <rick.wertenbroek@xxxxxxxxx>
---
 drivers/pci/controller/pcie-rockchip-ep.c | 37 +++++++++++++++--------
 drivers/pci/controller/pcie-rockchip.h    |  1 +
 2 files changed, 26 insertions(+), 12 deletions(-)

diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c
index a58c9d56b..b26f16bed 100644
--- a/drivers/pci/controller/pcie-rockchip-ep.c
+++ b/drivers/pci/controller/pcie-rockchip-ep.c
@@ -288,19 +288,31 @@ static void rockchip_pcie_ep_unmap_addr(struct pci_epc *epc, u8 fn, u8 vfn,
 }
 
 static int rockchip_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 vfn,
-				    u8 multi_msg_cap)
+				    u8 mmc)
 {
 	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
 	struct rockchip_pcie *rockchip = &ep->rockchip;
-	u16 flags;
+	u32 flags;
+	u32 multi_msg_cap;
+
+	if (fn) {
+		dev_err(&epc->dev, "This endpoint controller only supports a single physical function\n");
+		return -EINVAL;
+	}
+
+	if (mmc > 0x5) {
+		dev_err(&epc->dev, "Number of MSI IRQs cannot be more than 32\n");
+		return -EINVAL;
+	}
 
 	flags = rockchip_pcie_read(rockchip,
 				   ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
 				   ROCKCHIP_PCIE_EP_MSI_CTRL_REG);
 	flags &= ~ROCKCHIP_PCIE_EP_MSI_CTRL_MMC_MASK;
+	multi_msg_cap = mmc;
 	flags |=
-	   ((multi_msg_cap << 1) <<  ROCKCHIP_PCIE_EP_MSI_CTRL_MMC_OFFSET) |
-	   PCI_MSI_FLAGS_64BIT;
+	   (multi_msg_cap << ROCKCHIP_PCIE_EP_MSI_CTRL_MMC_OFFSET) |
+	   (PCI_MSI_FLAGS_64BIT << ROCKCHIP_PCIE_EP_MSI_FLAGS_OFFSET);
 	flags &= ~ROCKCHIP_PCIE_EP_MSI_CTRL_MASK_MSI_CAP;
 	rockchip_pcie_write(rockchip, flags,
 			    ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
@@ -312,7 +324,7 @@ static int rockchip_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn)
 {
 	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
 	struct rockchip_pcie *rockchip = &ep->rockchip;
-	u16 flags;
+	u32 flags;
 
 	flags = rockchip_pcie_read(rockchip,
 				   ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
@@ -380,9 +392,10 @@ static int rockchip_pcie_ep_send_msi_irq(struct rockchip_pcie_ep *ep, u8 fn,
 					 u8 interrupt_num)
 {
 	struct rockchip_pcie *rockchip = &ep->rockchip;
-	u16 flags, mme, data, data_mask;
+	u32 flags, mme, data, data_mask;
 	u8 msi_count;
 	u64 pci_addr, pci_addr_mask = 0xff;
+	u32 r;
 
 	/* Check MSI enable bit */
 	flags = rockchip_pcie_read(&ep->rockchip,
@@ -416,16 +429,16 @@ static int rockchip_pcie_ep_send_msi_irq(struct rockchip_pcie_ep *ep, u8 fn,
 				       ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
 				       ROCKCHIP_PCIE_EP_MSI_CTRL_REG +
 				       PCI_MSI_ADDRESS_LO);
-	pci_addr &= GENMASK_ULL(63, 2);
 
 	/* Set the outbound region if needed. */
 	if (unlikely(ep->irq_pci_addr != (pci_addr & ~pci_addr_mask) ||
 		     ep->irq_pci_fn != fn)) {
-		rockchip_pcie_prog_ep_ob_atu(rockchip, fn, ep->max_regions - 1,
-					     AXI_WRAPPER_MEM_WRITE,
-					     ep->irq_phys_addr,
-					     pci_addr & ~pci_addr_mask,
-					     pci_addr_mask + 1);
+		r = (ep->irq_phys_addr >> ilog2(SZ_1M)) & 0x1f;
+		rockchip_pcie_prog_ep_ob_atu(rockchip, fn, r,
+					AXI_WRAPPER_MEM_WRITE,
+					ep->irq_phys_addr,
+					pci_addr & ~pci_addr_mask,
+					pci_addr_mask + 1);
 		ep->irq_pci_addr = (pci_addr & ~pci_addr_mask);
 		ep->irq_pci_fn = fn;
 	}
diff --git a/drivers/pci/controller/pcie-rockchip.h b/drivers/pci/controller/pcie-rockchip.h
index e90c2a2b8..11dbf53cd 100644
--- a/drivers/pci/controller/pcie-rockchip.h
+++ b/drivers/pci/controller/pcie-rockchip.h
@@ -227,6 +227,7 @@
 #define ROCKCHIP_PCIE_EP_CMD_STATUS			0x4
 #define   ROCKCHIP_PCIE_EP_CMD_STATUS_IS		BIT(19)
 #define ROCKCHIP_PCIE_EP_MSI_CTRL_REG			0x90
+#define   ROCKCHIP_PCIE_EP_MSI_FLAGS_OFFSET			16
 #define   ROCKCHIP_PCIE_EP_MSI_CTRL_MMC_OFFSET		17
 #define   ROCKCHIP_PCIE_EP_MSI_CTRL_MMC_MASK		GENMASK(19, 17)
 #define   ROCKCHIP_PCIE_EP_MSI_CTRL_MME_OFFSET		20
-- 
2.25.1