Commit c4102c92 authored by Bjorn Helgaas's avatar Bjorn Helgaas

PCI: tegra: Remove top-level resource from hierarchy

41534e53 ("PCI: tegra: Implement a proper resource hierarchy") did two
things:

  1) It added a top-level resource that encloses all resources declared in
     the DT description, including registers and bridge apertures, and

  2) It requested the bridge apertures, which means the PCI core can track
     the resources used by PCI devices below the bridge.

The latter is necessary, but the former is questionable because there's no
guarantee that the bridge registers and the apertures are contiguous.  In
this example:

  # cat /proc/iomem
  00000000-3fffffff : /pcie-controller@00003000
    00000000-00000fff : /pcie-controller@00003000/pci@1,0
    00003000-000037ff : pads
    00003800-000039ff : afi
    10000000-1fffffff : cs

the resource tree claims that [mem 0x00003a00-0x0fffffff] is consumed by
/pcie-controller@00003000, but it's not mentioned in the DT, and it might
actually be used by other devices.

Remove the top-level resource so we don't claim more than the device
actually consumes.

This reintroduces the problem that we can't match the resources, e.g.,
"pads", "afi", "cs", etc., to the DT device.  I think this should be solved
by having the DT core request all resources of all devices in the DT (it
does not do that today).  If a driver claims the device, it can request the
resources it uses.  For example:

  # cat /proc/iomem
  00000000-00000fff : /pcie-controller@00003000
    00000000-00000fff : /pcie-controller@00003000/pci@1,0
  00003000-000037ff : /pcie-controller@00003000
    00003000-000037ff : pads
  00003800-000039ff : /pcie-controller@00003000
    00003800-000039ff : afi
  10000000-1fffffff : /pcie-controller@00003000
    10000000-1fffffff : cs
  ...
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 4c540a35
...@@ -274,7 +274,6 @@ struct tegra_pcie { ...@@ -274,7 +274,6 @@ struct tegra_pcie {
struct list_head buses; struct list_head buses;
struct resource *cs; struct resource *cs;
struct resource all;
struct resource io; struct resource io;
struct resource pio; struct resource pio;
struct resource mem; struct resource mem;
...@@ -623,7 +622,7 @@ static int tegra_pcie_setup(int nr, struct pci_sys_data *sys) ...@@ -623,7 +622,7 @@ static int tegra_pcie_setup(int nr, struct pci_sys_data *sys)
sys->mem_offset = pcie->offset.mem; sys->mem_offset = pcie->offset.mem;
sys->io_offset = pcie->offset.io; sys->io_offset = pcie->offset.io;
err = devm_request_resource(pcie->dev, &pcie->all, &pcie->io); err = devm_request_resource(pcie->dev, &iomem_resource, &pcie->io);
if (err < 0) if (err < 0)
return err; return err;
...@@ -631,11 +630,11 @@ static int tegra_pcie_setup(int nr, struct pci_sys_data *sys) ...@@ -631,11 +630,11 @@ static int tegra_pcie_setup(int nr, struct pci_sys_data *sys)
if (err < 0) if (err < 0)
return err; return err;
err = devm_request_resource(pcie->dev, &pcie->all, &pcie->mem); err = devm_request_resource(pcie->dev, &iomem_resource, &pcie->mem);
if (err < 0) if (err < 0)
return err; return err;
err = devm_request_resource(pcie->dev, &pcie->all, &pcie->prefetch); err = devm_request_resource(pcie->dev, &iomem_resource, &pcie->prefetch);
if (err) if (err)
return err; return err;
...@@ -1822,12 +1821,6 @@ static int tegra_pcie_parse_dt(struct tegra_pcie *pcie) ...@@ -1822,12 +1821,6 @@ static int tegra_pcie_parse_dt(struct tegra_pcie *pcie)
struct resource res; struct resource res;
int err; int err;
memset(&pcie->all, 0, sizeof(pcie->all));
pcie->all.flags = IORESOURCE_MEM;
pcie->all.name = np->full_name;
pcie->all.start = ~0;
pcie->all.end = 0;
if (of_pci_range_parser_init(&parser, np)) { if (of_pci_range_parser_init(&parser, np)) {
dev_err(pcie->dev, "missing \"ranges\" property\n"); dev_err(pcie->dev, "missing \"ranges\" property\n");
return -EINVAL; return -EINVAL;
...@@ -1880,18 +1873,8 @@ static int tegra_pcie_parse_dt(struct tegra_pcie *pcie) ...@@ -1880,18 +1873,8 @@ static int tegra_pcie_parse_dt(struct tegra_pcie *pcie)
} }
break; break;
} }
if (res.start <= pcie->all.start)
pcie->all.start = res.start;
if (res.end >= pcie->all.end)
pcie->all.end = res.end;
} }
err = devm_request_resource(pcie->dev, &iomem_resource, &pcie->all);
if (err < 0)
return err;
err = of_pci_parse_bus_range(np, &pcie->busn); err = of_pci_parse_bus_range(np, &pcie->busn);
if (err < 0) { if (err < 0) {
dev_err(pcie->dev, "failed to parse ranges property: %d\n", dev_err(pcie->dev, "failed to parse ranges property: %d\n",
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment