Re: [PATCH v4 4/5] PCI: Try best to allocate pref mmio 64bit above 4g

From: Guo Chao
Date: Mon Dec 16 2013 - 03:23:49 EST


On Mon, Dec 09, 2013 at 10:54:43PM -0800, Yinghai Lu wrote:
> When one of children resources does not support MEM_64, MEM_64 for
> bridge get reset, so pull down whole pref resource on the bridge under 4G.
>
> If the bridge support pref mem 64, will only allocate that with pref mem64 to
> children that support it.
> For children resources if they only support pref mem 32, will allocate them
> from non pref mem instead.
>
> If the bridge only support 32bit pref mmio, will still have all children pref
> mmio under that.
>
> -v2: Add release bridge res support with bridge mem res for pref_mem children res.
> -v3: refresh and make it can be applied early before for_each_dev_res patchset.
>
> Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
> Tested-by: Guo Chao <yan@xxxxxxxxxxxxxxxxxx>
> ---
> drivers/pci/setup-bus.c | 133 ++++++++++++++++++++++++++++++++----------------
> drivers/pci/setup-res.c | 14 ++++-
> 2 files changed, 101 insertions(+), 46 deletions(-)
>
> diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
> index 7933982..843764e 100644
> --- a/drivers/pci/setup-bus.c
> +++ b/drivers/pci/setup-bus.c
> @@ -711,12 +711,11 @@ static void pci_bridge_check_ranges(struct pci_bus *bus)
> bus resource of a given type. Note: we intentionally skip
> the bus resources which have already been assigned (that is,
> have non-NULL parent resource). */
> -static struct resource *find_free_bus_resource(struct pci_bus *bus, unsigned long type)
> +static struct resource *find_free_bus_resource(struct pci_bus *bus,
> + unsigned long type_mask, unsigned long type)
> {
> int i;
> struct resource *r;
> - unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
> - IORESOURCE_PREFETCH;
>
> pci_bus_for_each_resource(bus, r, i) {
> if (r == &ioport_resource || r == &iomem_resource)
> @@ -813,7 +812,8 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
> resource_size_t add_size, struct list_head *realloc_head)
> {
> struct pci_dev *dev;
> - struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
> + struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO,
> + IORESOURCE_IO);
> resource_size_t size = 0, size0 = 0, size1 = 0;
> resource_size_t children_add_size = 0;
> resource_size_t min_align, align;
> @@ -913,15 +913,16 @@ static inline resource_size_t calculate_mem_align(resource_size_t *aligns,
> * guarantees that all child resources fit in this size.
> */
> static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
> - unsigned long type, resource_size_t min_size,
> - resource_size_t add_size,
> - struct list_head *realloc_head)
> + unsigned long type, unsigned long type2,
> + resource_size_t min_size, resource_size_t add_size,
> + struct list_head *realloc_head)
> {
> struct pci_dev *dev;
> resource_size_t min_align, align, size, size0, size1;
> resource_size_t aligns[12]; /* Alignments from 1Mb to 2Gb */
> int order, max_order;
> - struct resource *b_res = find_free_bus_resource(bus, type);
> + struct resource *b_res = find_free_bus_resource(bus,
> + mask | IORESOURCE_PREFETCH, type);
> unsigned int mem64_mask = 0;
> resource_size_t children_add_size = 0;
>
> @@ -942,7 +943,8 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
> struct resource *r = &dev->resource[i];
> resource_size_t r_size;
>
> - if (r->parent || (r->flags & mask) != type)
> + if (r->parent || ((r->flags & mask) != type &&
> + (r->flags & mask) != type2))
> continue;
> r_size = resource_size(r);
> #ifdef CONFIG_PCI_IOV
> @@ -1115,8 +1117,9 @@ void __ref __pci_bus_size_bridges(struct pci_bus *bus,
> struct list_head *realloc_head)
> {
> struct pci_dev *dev;
> - unsigned long mask, prefmask;
> + unsigned long mask, prefmask, type2 = 0;
> resource_size_t additional_mem_size = 0, additional_io_size = 0;
> + struct resource *b_res;
>
> list_for_each_entry(dev, &bus->devices, bus_list) {
> struct pci_bus *b = dev->subordinate;
> @@ -1161,15 +1164,31 @@ void __ref __pci_bus_size_bridges(struct pci_bus *bus,
> has already been allocated by arch code, try
> non-prefetchable range for both types of PCI memory
> resources. */
> + b_res = &bus->self->resource[PCI_BRIDGE_RESOURCES];
> mask = IORESOURCE_MEM;
> prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
> - if (pbus_size_mem(bus, prefmask, prefmask,
> + if (b_res[2].flags & IORESOURCE_MEM_64) {
> + prefmask |= IORESOURCE_MEM_64;
> + if (pbus_size_mem(bus, prefmask, prefmask, prefmask,
> realloc_head ? 0 : additional_mem_size,
> - additional_mem_size, realloc_head))
> - mask = prefmask; /* Success, size non-prefetch only. */
> - else
> - additional_mem_size += additional_mem_size;
> - pbus_size_mem(bus, mask, IORESOURCE_MEM,
> + additional_mem_size, realloc_head)) {
> + /* Success, size non-pref64 only. */
> + mask = prefmask;
> + type2 = prefmask & ~IORESOURCE_MEM_64;
> + }
> + }
> + if (!type2) {
> + prefmask &= ~IORESOURCE_MEM_64;
> + if (pbus_size_mem(bus, prefmask, prefmask, prefmask,
> + realloc_head ? 0 : additional_mem_size,
> + additional_mem_size, realloc_head)) {
> + /* Success, size non-prefetch only. */
> + mask = prefmask;
> + } else
> + additional_mem_size += additional_mem_size;
> + type2 = IORESOURCE_MEM;
> + }
> + pbus_size_mem(bus, mask, IORESOURCE_MEM, type2,
> realloc_head ? 0 : additional_mem_size,
> additional_mem_size, realloc_head);
> break;


64-bit non-prefetchable BARs are missed from caculation in the scheme,
causing assign failed eventually.

[ 0.350882] pci 0002:00:00.0: BAR 14: assigned [mem
0x3d04080000000-0x3d04080
7fffff]
[ 0.350941] pci 0002:01:00.4: BAR 2: assigned [mem
0x3d04080000000-0x3d040807fffff 64bit]
[ 0.351009] pci 0002:01:00.0: BAR 0: can't assign mem (size 0x40000)
[ 0.351055] pci 0002:01:00.0: BAR 6: can't assign mem pref (size
0x40000)
[ 0.351101] pci 0002:01:00.1: BAR 0: can't assign mem (size 0x40000)
[ 0.351148] pci 0002:01:00.1: BAR 6: can't assign mem pref (size
0x40000)
[ 0.351195] pci 0002:01:00.2: BAR 0: can't assign mem (size 0x40000)
[ 0.351241] pci 0002:01:00.2: BAR 6: can't assign mem pref (size
0x40000)
[ 0.351286] pci 0002:01:00.3: BAR 0: can't assign mem (size 0x40000)
[ 0.351335] pci 0002:01:00.3: BAR 6: can't assign mem pref (size
0x40000)
[ 0.351382] pci 0002:01:00.4: BAR 0: can't assign mem (size 0x40000)
[ 0.351428] pci 0002:01:00.5: BAR 0: can't assign mem (size 0x40000)
[ 0.351473] pci 0002:01:00.6: BAR 0: can't assign mem (size 0x40000)
[ 0.351519] pci 0002:01:00.0: BAR 4: can't assign mem (size 0x2000)
[ 0.351604] pci 0002:01:00.1: BAR 4: can't assign mem (size 0x2000)
[ 0.351696] pci 0002:01:00.2: BAR 4: can't assign mem (size 0x2000)
[ 0.351789] pci 0002:01:00.3: BAR 4: can't assign mem (size 0x2000)
[ 0.351882] pci 0002:01:00.4: BAR 4: can't assign mem (size 0x2000)
[ 0.351974] pci 0002:01:00.5: BAR 4: can't assign mem (size 0x2000)
[ 0.352067] pci 0002:01:00.6: BAR 4: can't assign mem (size 0x2000)


Though I remember 64-bit BAR should always be prefetchable ... ...

Will you figure out a better way to cover them or just add a 'type3' parameter?

Thanks,
Guo Chao

> @@ -1255,42 +1274,66 @@ static void __ref __pci_bridge_assign_resources(const struct pci_dev *bridge,
> static void pci_bridge_release_resources(struct pci_bus *bus,
> unsigned long type)
> {
> - int idx;
> - bool changed = false;
> - struct pci_dev *dev;
> + struct pci_dev *dev = bus->self;
> struct resource *r;
> unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
> - IORESOURCE_PREFETCH;
> + IORESOURCE_PREFETCH | IORESOURCE_MEM_64;
> + unsigned old_flags = 0;
> + struct resource *b_res;
> + int idx = 1;
>
> - dev = bus->self;
> - for (idx = PCI_BRIDGE_RESOURCES; idx <= PCI_BRIDGE_RESOURCE_END;
> - idx++) {
> - r = &dev->resource[idx];
> - if ((r->flags & type_mask) != type)
> - continue;
> - if (!r->parent)
> - continue;
> - /*
> - * if there are children under that, we should release them
> - * all
> - */
> - release_child_resources(r);
> - if (!release_resource(r)) {
> - dev_printk(KERN_DEBUG, &dev->dev,
> - "resource %d %pR released\n", idx, r);
> - /* keep the old size */
> - r->end = resource_size(r) - 1;
> - r->start = 0;
> - r->flags = 0;
> - changed = true;
> - }
> - }
> + b_res = &dev->resource[PCI_BRIDGE_RESOURCES];
> +
> + /*
> + * 1. if there is io port assign fail, will release bridge
> + * io port.
> + * 2. if there is non pref mmio assign fail, release bridge
> + * nonpref mmio.
> + * 3. if there is 64bit pref mmio assign fail, and bridge pref
> + * is 64bit, release bridge pref mmio.
> + * 4. if there is pref mmio assign fail, and bridge pref is
> + * 32bit mmio, release bridge pref mmio
> + * 5. if there is pref mmio assign fail, and bridge pref is not
> + * assigned, release bridge nonpref mmio.
> + */
> + if (type & IORESOURCE_IO)
> + idx = 0;
> + else if (!(type & IORESOURCE_PREFETCH))
> + idx = 1;
> + else if ((type & IORESOURCE_MEM_64) &&
> + (b_res[2].flags & IORESOURCE_MEM_64))
> + idx = 2;
> + else if (!(b_res[2].flags & IORESOURCE_MEM_64) &&
> + (b_res[2].flags & IORESOURCE_PREFETCH))
> + idx = 2;
> + else
> + idx = 1;
> +
> + r = &b_res[idx];
> +
> + if (!r->parent)
> + return;
> +
> + /*
> + * if there are children under that, we should release them
> + * all
> + */
> + release_child_resources(r);
> + if (!release_resource(r)) {
> + type = old_flags = r->flags & type_mask;
> + dev_printk(KERN_DEBUG, &dev->dev, "resource %d %pR released\n",
> + PCI_BRIDGE_RESOURCES + idx, r);
> + /* keep the old size */
> + r->end = resource_size(r) - 1;
> + r->start = 0;
> + r->flags = 0;
>
> - if (changed) {
> /* avoiding touch the one without PREF */
> if (type & IORESOURCE_PREFETCH)
> type = IORESOURCE_PREFETCH;
> __pci_setup_bridge(bus, type);
> + /* for next child res under same bridge */
> + r->flags = old_flags;
> }
> }
>
> @@ -1469,7 +1512,7 @@ void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus)
> LIST_HEAD(fail_head);
> struct pci_dev_resource *fail_res;
> unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
> - IORESOURCE_PREFETCH;
> + IORESOURCE_PREFETCH | IORESOURCE_MEM_64;
> int pci_try_num = 1;
> enum enable_type enable_local;
>
> diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
> index 5c060b1..1a84f30 100644
> --- a/drivers/pci/setup-res.c
> +++ b/drivers/pci/setup-res.c
> @@ -208,9 +208,21 @@ static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
>
> /* First, try exact prefetching match.. */
> ret = pci_bus_alloc_resource(bus, res, size, align, min,
> - IORESOURCE_PREFETCH,
> + IORESOURCE_PREFETCH | IORESOURCE_MEM_64,
> pcibios_align_resource, dev);
>
> + if (ret < 0 &&
> + (res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64))) {
> + /*
> + * That failed.
> + *
> + * Try below 4g pref
> + */
> + ret = pci_bus_alloc_resource(bus, res, size, align, min,
> + IORESOURCE_PREFETCH,
> + pcibios_align_resource, dev);
> + }
> +
> if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
> /*
> * That failed.
> --
> 1.8.4
>

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