| Message ID | 20190626023746.94250-1-aik@ozlabs.ru (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | dead1c845dbe97e0061dae2017eaf3bd8f8f06ee |
| Headers | show |
| Series | [kernel,v2] powerpc/pci/of: Parse unassigned resources | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch next (c7d64b560ce80d8c44f082eee8352f0778a73195) |
| snowpatch_ozlabs/build-ppc64le | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64be | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64e | success | Build succeeded |
| snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 26 lines checked |
On Wed, 2019-06-26 at 02:37:46 UTC, Alexey Kardashevskiy wrote: > The pseries platform uses the PCI_PROBE_DEVTREE method of PCI probing > which reads "assigned-addresses" of every PCI device and initializes > the device resources. However if the property is missing or zero sized, > then there is no fallback of any kind and the PCI resources remain > undiscovered, i.e. pdev->resource[] array remains empty. > > This adds a fallback which parses the "reg" property in pretty much same > way except it marks resources as "unset" which later make Linux assign > those resources proper addresses. > > This has an effect when: > 1. a hypervisor failed to assign any resource for a device; > 2. /chosen/linux,pci-probe-only=0 is in the DT so the system may try > assigning a resource. > Neither is likely to happen under PowerVM. > > Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/dead1c845dbe97e0061dae2017eaf3bd8f8f06ee cheers
diff --git a/arch/powerpc/kernel/pci_of_scan.c b/arch/powerpc/kernel/pci_of_scan.c index 64ad92016b63..bd78f325a636 100644 --- a/arch/powerpc/kernel/pci_of_scan.c +++ b/arch/powerpc/kernel/pci_of_scan.c @@ -82,10 +82,16 @@ static void of_pci_parse_addrs(struct device_node *node, struct pci_dev *dev) const __be32 *addrs; u32 i; int proplen; + bool mark_unset = false; addrs = of_get_property(node, "assigned-addresses", &proplen); - if (!addrs) - return; + if (!addrs || !proplen) { + addrs = of_get_property(node, "reg", &proplen); + if (!addrs || !proplen) + return; + mark_unset = true; + } + pr_debug(" parse addresses (%d bytes) @ %p\n", proplen, addrs); for (; proplen >= 20; proplen -= 20, addrs += 5) { flags = pci_parse_of_flags(of_read_number(addrs, 1), 0); @@ -110,6 +116,8 @@ static void of_pci_parse_addrs(struct device_node *node, struct pci_dev *dev) continue; } res->flags = flags; + if (mark_unset) + res->flags |= IORESOURCE_UNSET; res->name = pci_name(dev); region.start = base; region.end = base + size - 1;
The pseries platform uses the PCI_PROBE_DEVTREE method of PCI probing which reads "assigned-addresses" of every PCI device and initializes the device resources. However if the property is missing or zero sized, then there is no fallback of any kind and the PCI resources remain undiscovered, i.e. pdev->resource[] array remains empty. This adds a fallback which parses the "reg" property in pretty much same way except it marks resources as "unset" which later make Linux assign those resources proper addresses. This has an effect when: 1. a hypervisor failed to assign any resource for a device; 2. /chosen/linux,pci-probe-only=0 is in the DT so the system may try assigning a resource. Neither is likely to happen under PowerVM. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> --- This is an attempts to boot linux directly under QEMU without slof/rtas; the aim is to use petitboot instead and let the guest kernel configure devices. QEMU does not allocate resources, it creates correct "reg" and zero length "assigned-addresses" (which is probably a bug on its own) which is normally populated by SLOF later but not during this exercise. --- Changes: v2: * updated commit log * fixed a bug with checking "addrs" which made the whole patch pointless * s/unset/mark_unset/ --- arch/powerpc/kernel/pci_of_scan.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)