[PATCH] PCI: dwc: Move allocate and map page for msi out of dw_pcie_msi_init()

Jisheng Zhang Jisheng.Zhang at synaptics.com
Wed Sep 23 02:26:07 EDT 2020


Currently, dw_pcie_msi_init() allocates and maps page for msi, then
program the PCIE_MSI_ADDR_LO and PCIE_MSI_ADDR_HI. The Root Complex
may lose power during suspend-to-RAM, so when we resume, we want to
redo the latter but not the former. If designware based driver (for
example, pcie-tegra194.c) calls dw_pcie_msi_init() in resume path, the
previous msi page will be leaked.

Move the allocate and map msi page from dw_pcie_msi_init() to
dw_pcie_host_init() to fix this problem.

Fixes: 56e15a238d92 ("PCI: tegra: Add Tegra194 PCIe support")
Signed-off-by: Jisheng Zhang <Jisheng.Zhang at synaptics.com>
---
 drivers/pci/controller/dwc/pci-dra7xx.c       | 18 ++++++++++++-
 .../pci/controller/dwc/pcie-designware-host.c | 27 +++++++++----------
 2 files changed, 30 insertions(+), 15 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
index dc387724cf08..4301cf844a4c 100644
--- a/drivers/pci/controller/dwc/pci-dra7xx.c
+++ b/drivers/pci/controller/dwc/pci-dra7xx.c
@@ -490,7 +490,9 @@ static struct irq_chip dra7xx_pci_msi_bottom_irq_chip = {
 static int dra7xx_pcie_msi_host_init(struct pcie_port *pp)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct device *dev = pci->dev;
 	u32 ctrl, num_ctrls;
+	int ret;
 
 	pp->msi_irq_chip = &dra7xx_pci_msi_bottom_irq_chip;
 
@@ -506,7 +508,21 @@ static int dra7xx_pcie_msi_host_init(struct pcie_port *pp)
 				    ~0);
 	}
 
-	return dw_pcie_allocate_domains(pp);
+	ret = dw_pcie_allocate_domains(pp);
+	if (ret)
+		return ret;
+
+	pp->msi_page = alloc_page(GFP_KERNEL);
+	pp->msi_data = dma_map_page(dev, pp->msi_page, 0, PAGE_SIZE,
+				    DMA_FROM_DEVICE);
+	ret = dma_mapping_error(dev, pp->msi_data);
+	if (ret) {
+		dev_err(dev, "Failed to map MSI data\n");
+		__free_page(pp->msi_page);
+		pp->msi_page = NULL;
+		dw_pcie_free_msi(pp);
+	}
+	return ret;
 }
 
 static const struct dw_pcie_host_ops dra7xx_pcie_host_ops = {
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 9dafecba347f..c23ba64f64fe 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -294,20 +294,7 @@ void dw_pcie_free_msi(struct pcie_port *pp)
 
 void dw_pcie_msi_init(struct pcie_port *pp)
 {
-	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
-	struct device *dev = pci->dev;
-	u64 msi_target;
-
-	pp->msi_page = alloc_page(GFP_KERNEL);
-	pp->msi_data = dma_map_page(dev, pp->msi_page, 0, PAGE_SIZE,
-				    DMA_FROM_DEVICE);
-	if (dma_mapping_error(dev, pp->msi_data)) {
-		dev_err(dev, "Failed to map MSI data\n");
-		__free_page(pp->msi_page);
-		pp->msi_page = NULL;
-		return;
-	}
-	msi_target = (u64)pp->msi_data;
+	u64 msi_target = (u64)pp->msi_data;
 
 	/* Program the msi_data */
 	dw_pcie_wr_own_conf(pp, PCIE_MSI_ADDR_LO, 4,
@@ -440,6 +427,18 @@ int dw_pcie_host_init(struct pcie_port *pp)
 				irq_set_chained_handler_and_data(pp->msi_irq,
 							    dw_chained_msi_isr,
 							    pp);
+
+			pp->msi_page = alloc_page(GFP_KERNEL);
+			pp->msi_data = dma_map_page(pci->dev, pp->msi_page,
+						    0, PAGE_SIZE,
+						    DMA_FROM_DEVICE);
+			ret = dma_mapping_error(pci->dev, pp->msi_data);
+			if (ret) {
+				dev_err(pci->dev, "Failed to map MSI data\n");
+				__free_page(pp->msi_page);
+				pp->msi_page = NULL;
+				goto err_free_msi;
+			}
 		} else {
 			ret = pp->ops->msi_host_init(pp);
 			if (ret < 0)
-- 
2.28.0




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