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

From: Jisheng Zhang
Date: Wed Sep 23 2020 - 02:27:31 EST


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@xxxxxxxxxxxxx>
---
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