diff options
| -rw-r--r-- | drivers/pci/host/pci-tegra.c | 33 |
1 files changed, 21 insertions, 12 deletions
diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c index 0dadb81eca70..b3722b7709df 100644 --- a/drivers/pci/host/pci-tegra.c +++ b/drivers/pci/host/pci-tegra.c @@ -233,8 +233,8 @@ struct tegra_msi { struct msi_controller chip; DECLARE_BITMAP(used, INT_PCI_MSI_NR); struct irq_domain *domain; - unsigned long pages; struct mutex lock; + u64 phys; int irq; }; @@ -1448,9 +1448,8 @@ static int tegra_msi_setup_irq(struct msi_controller *chip, irq_set_msi_desc(irq, desc); - msg.address_lo = virt_to_phys((void *)msi->pages); - /* 32 bit address only */ - msg.address_hi = 0; + msg.address_lo = lower_32_bits(msi->phys); + msg.address_hi = upper_32_bits(msi->phys); msg.data = hwirq; pci_write_msi_msg(irq, &msg); @@ -1499,7 +1498,6 @@ static int tegra_pcie_enable_msi(struct tegra_pcie *pcie) const struct tegra_pcie_soc *soc = pcie->soc; struct tegra_msi *msi = &pcie->msi; struct device *dev = pcie->dev; - unsigned long base; int err; u32 reg; @@ -1531,12 +1529,25 @@ static int tegra_pcie_enable_msi(struct tegra_pcie *pcie) goto err; } - /* setup AFI/FPCI range */ - msi->pages = __get_free_pages(GFP_KERNEL, 0); - base = virt_to_phys((void *)msi->pages); + /* + * The PCI host bridge on Tegra contains some logic that intercepts + * MSI writes, which means that the MSI target address doesn't have + * to point to actual physical memory. Rather than allocating one 4 + * KiB page of system memory that's never used, we can simply pick + * an arbitrary address within an area reserved for system memory + * in the FPCI address map. + * + * However, in order to avoid confusion, we pick an address that + * doesn't map to physical memory. The FPCI address map reserves a + * 1012 GiB region for system memory and memory-mapped I/O. Since + * none of the Tegra SoCs that contain this PCI host bridge can + * address more than 16 GiB of system memory, the last 4 KiB of + * these 1012 GiB is a good candidate. + */ + msi->phys = 0xfcfffff000; - afi_writel(pcie, base >> soc->msi_base_shift, AFI_MSI_FPCI_BAR_ST); - afi_writel(pcie, base, AFI_MSI_AXI_BAR_ST); + afi_writel(pcie, msi->phys >> soc->msi_base_shift, AFI_MSI_FPCI_BAR_ST); + afi_writel(pcie, msi->phys, AFI_MSI_AXI_BAR_ST); /* this register is in 4K increments */ afi_writel(pcie, 1, AFI_MSI_BAR_SZ); @@ -1585,8 +1596,6 @@ static int tegra_pcie_disable_msi(struct tegra_pcie *pcie) afi_writel(pcie, 0, AFI_MSI_EN_VEC6); afi_writel(pcie, 0, AFI_MSI_EN_VEC7); - free_pages(msi->pages, 0); - if (msi->irq > 0) free_irq(msi->irq, pcie); |