On Wed, 3 Jun 2015 16:55:56 +0530
Nikunj A Dadhania <nik...@linux.vnet.ibm.com> wrote:
> Each hardware instance has a platform unique location code. The OF
> device tree that describes a part of a hardware entity must include
> the “ibm,loc-code” property with a value that represents the location
> code for that hardware entity.
>
> Populate ibm,loc-code.
>
> 1) PCI passthru devices need to identify with its own ibm,loc-code
> available on the host. In failure cases use:
> vfio_<name>:<phb-index>:<bus>:<slot>.<fn>
>
> 2) Emulated devices encode as following:
> qemu_<name>:<phb-index>:<bus>:<slot>.<fn>
>
> Signed-off-by: Nikunj A Dadhania <nik...@linux.vnet.ibm.com>
> ---
> hw/ppc/spapr_pci.c | 78
> +++++++++++++++++++++++++++++++++++++++++++++++-------
> 1 file changed, 68 insertions(+), 10 deletions(-)
>
> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
> index 4226468..986bb21 100644
> --- a/hw/ppc/spapr_pci.c
> +++ b/hw/ppc/spapr_pci.c
> @@ -746,6 +746,60 @@ static AddressSpace *spapr_pci_dma_iommu(PCIBus *bus,
> void *opaque, int devfn)
> return &phb->iommu_as;
> }
>
> +static char *spapr_phb_vfio_get_loc_code(sPAPRPHBState *sphb, PCIDevice
> *pdev)
> +{
> + char *path = NULL, *buf = NULL, *host = NULL;
> +
> + /* Get the PCI VFIO host id */
> + host = object_property_get_str(OBJECT(pdev), "host", NULL);
> + if (!host) {
> + goto err_out;
> + }
> +
> + /* Construct the path of the file that will give us the DT location */
> + path = g_strdup_printf("/sys/bus/pci/devices/%s/devspec", host);
> + g_free(host);
> + if (!path || !g_file_get_contents(path, &buf, NULL, NULL)) {
> + goto err_out;
> + }
> + g_free(path);
> +
> + /* Construct and read from host device tree the loc-code */
> + path = g_strdup_printf("/proc/device-tree%s/ibm,loc-code", buf);
> + g_free(buf);
> + if (!path || !g_file_get_contents(path, &buf, NULL, NULL)) {
> + goto err_out;
> + }
> + return buf;
I'd maybe change the above 4 lines into:
if (path && g_file_get_contents(path, &buf, NULL, NULL)) {
return buf;
}
so that you can get rid of one goto here.
> +err_out:
> + g_free(path);
> + return NULL;
> +}
> +
> +static char *spapr_phb_get_loc_code(sPAPRPHBState *sphb, PCIDevice *pdev)
> +{
> + char *buf;
> + const char *devtype = "qemu";
> + uint32_t busnr = pci_bus_num(PCI_BUS(qdev_get_parent_bus(DEVICE(pdev))));
> +
> + if (object_dynamic_cast(OBJECT(pdev), "vfio-pci")) {
> + buf = spapr_phb_vfio_get_loc_code(sphb, pdev);
> + if (buf) {
> + return buf;
> + }
> + devtype = "vfio";
> + }
> + /*
> + * For emulated devices and VFIO-failure case, make up
> + * the loc-code.
> + */
> + buf = g_strdup_printf("%s_%s:%04x:%02x:%02x.%x",
> + devtype, pdev->name, sphb->index, busnr,
> + PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn));
> + return buf;
> +}
> +
> /* Macros to operate with address in OF binding to PCI */
> #define b_x(x, p, l) (((x) & ((1<<(l))-1)) << (p))
> #define b_n(x) b_x((x), 31, 1) /* 0 if relocatable */
> @@ -884,11 +938,12 @@ static void populate_resource_props(PCIDevice *d,
> ResourceProps *rp)
>
> static int spapr_populate_pci_child_dt(PCIDevice *dev, void *fdt, int offset,
> int phb_index, int drc_index,
> - const char *drc_name)
> + sPAPRPHBState *sphb)
> {
> ResourceProps rp;
> bool is_bridge = false;
> int pci_status;
> + char *buf = NULL;
Is the "= NULL" required here? If not, please remove, newer version
of gcc tend to complain otherwise.
> if (pci_default_read_config(dev, PCI_HEADER_TYPE, 1) ==
> PCI_HEADER_TYPE_BRIDGE) {
> @@ -949,10 +1004,15 @@ static int spapr_populate_pci_child_dt(PCIDevice *dev,
> void *fdt, int offset,
> * processed by OF beforehand
> */
> _FDT(fdt_setprop_string(fdt, offset, "name", "pci"));
> - if (drc_name) {
> - _FDT(fdt_setprop(fdt, offset, "ibm,loc-code", drc_name,
> - strlen(drc_name)));
> + buf = spapr_phb_get_loc_code(sphb, dev);
> + if (!buf) {
> + error_report("Failed setting the ibm,loc-code");
> + return -1;
> }
> +
> + _FDT(fdt_setprop_string(fdt, offset, "ibm,loc-code", buf));
I wonder whether this will cause some Coverity warnings later ...
the _FDT macro can return immediately (ugh, return in a macro ... IMHO
a bad idea...). buf is not freed in that case, and that might trigger a
warning...
> + g_free(buf);
> +
> if (drc_index) {
> _FDT(fdt_setprop_cell(fdt, offset, "ibm,my-drc-index", drc_index));
> }
[...]
Thomas
