Commit 5106787a authored by Thierry Reding's avatar Thierry Reding Committed by Bjorn Helgaas
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PCI: tegra: Use physical range for I/O mapping 



Commit 0b0b0893 ("of/pci: Fix the conversion of IO ranges into IO
resources") changed how I/O resources are parsed from DT.  Rather than
containing the physical address of the I/O region, the addresses will now
be in I/O address space.

On Tegra the union of all ranges is used to expose a top-level memory-
mapped resource for the PCI host bridge.  This helps to make /proc/iomem
more readable.

Combining both of the above, the union would now include the I/O space
region.  This causes a regression on Tegra20, where the physical base
address of the PCIe controller (and therefore of the union) is located at
physical address 0x80000000.  Since I/O space starts at 0, the union will
now include all of system RAM which starts at 0x00000000.

This commit fixes this by keeping two copies of the I/O range: one that
represents the range in the CPU's physical address space, the other for the
range in the I/O address space.  This allows the translation setup within
the driver to reuse the physical addresses.  The code registering the I/O
region with the PCI core uses both ranges to establish the mapping.

Fixes: 0b0b0893 ("of/pci: Fix the conversion of IO ranges into IO resources")
Reported-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Tested-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Suggested-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarArnd Bergmann <arnd@arndb.de>
parent 7fc986d8

drivers/pci/host/pci-tegra.c

+20 −8
Original line number Diff line number Diff line
@@ -276,6 +276,7 @@ struct tegra_pcie { 


	struct resource all;

	struct resource io;

	struct resource pio;

	struct resource mem;

	struct resource prefetch;

	struct resource busn;
@@ -658,7 +659,6 @@ static int tegra_pcie_setup(int nr, struct pci_sys_data *sys) 
{

	struct tegra_pcie *pcie = sys_to_pcie(sys);

	int err;

	phys_addr_t io_start;



	err = devm_request_resource(pcie->dev, &pcie->all, &pcie->mem);

	if (err < 0)
@@ -668,14 +668,12 @@ static int tegra_pcie_setup(int nr, struct pci_sys_data *sys) 
	if (err)

		return err;



	io_start = pci_pio_to_address(pcie->io.start);



	pci_add_resource_offset(&sys->resources, &pcie->mem, sys->mem_offset);

	pci_add_resource_offset(&sys->resources, &pcie->prefetch,

				sys->mem_offset);

	pci_add_resource(&sys->resources, &pcie->busn);



	pci_ioremap_io(nr * SZ_64K, io_start);

	pci_ioremap_io(pcie->pio.start, pcie->io.start);



	return 1;

}
@@ -786,7 +784,6 @@ static irqreturn_t tegra_pcie_isr(int irq, void *arg) 
static void tegra_pcie_setup_translations(struct tegra_pcie *pcie)

{

	u32 fpci_bar, size, axi_address;

	phys_addr_t io_start = pci_pio_to_address(pcie->io.start);



	/* Bar 0: type 1 extended configuration space */

	fpci_bar = 0xfe100000;
@@ -799,7 +796,7 @@ static void tegra_pcie_setup_translations(struct tegra_pcie *pcie) 
	/* Bar 1: downstream IO bar */

	fpci_bar = 0xfdfc0000;

	size = resource_size(&pcie->io);

	axi_address = io_start;

	axi_address = pcie->io.start;

	afi_writel(pcie, axi_address, AFI_AXI_BAR1_START);

	afi_writel(pcie, size >> 12, AFI_AXI_BAR1_SZ);

	afi_writel(pcie, fpci_bar, AFI_FPCI_BAR1);
@@ -1690,8 +1687,23 @@ static int tegra_pcie_parse_dt(struct tegra_pcie *pcie) 


		switch (res.flags & IORESOURCE_TYPE_BITS) {

		case IORESOURCE_IO:

			memcpy(&pcie->io, &res, sizeof(res));

			pcie->io.name = np->full_name;

			memcpy(&pcie->pio, &res, sizeof(res));

			pcie->pio.name = np->full_name;



			/*

			 * The Tegra PCIe host bridge uses this to program the

			 * mapping of the I/O space to the physical address,

			 * so we override the .start and .end fields here that

			 * of_pci_range_to_resource() converted to I/O space.

			 * We also set the IORESOURCE_MEM type to clarify that

			 * the resource is in the physical memory space.

			 */

			pcie->io.start = range.cpu_addr;

			pcie->io.end = range.cpu_addr + range.size - 1;

			pcie->io.flags = IORESOURCE_MEM;

			pcie->io.name = "I/O";



			memcpy(&res, &pcie->io, sizeof(res));

			break;



		case IORESOURCE_MEM:

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