Re: [PATCH v2 1/1] PCI: Add hp_mmio_size and hp_mmio_pref_size parameters

From: Bjorn Helgaas
Date: Wed Oct 23 2019 - 10:27:20 EST


On Wed, Oct 23, 2019 at 12:12:29PM +0000, Nicholas Johnson wrote:
> Add kernel parameter pci=hpmmiosize=nn[KMG] to set MMIO bridge window
> size for hotplug bridges.
>
> Add kernel parameter pci=hpmmioprefsize=nn[KMG] to set MMIO_PREF bridge
> window size for hotplug bridges.
>
> Leave pci=hpmemsize=nn[KMG] unchanged, to prevent disruptions to
> existing users. This sets both MMIO and MMIO_PREF to the same size.
>
> The two new parameters conform to the style of pci=hpiosize=nn[KMG].
>
> Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@xxxxxxxxxxxxxx>

Applied to pci/resource for v5.5, thanks!

> ---
> .../admin-guide/kernel-parameters.txt | 9 ++++++-
> drivers/pci/pci.c | 13 +++++++---
> drivers/pci/pci.h | 3 ++-
> drivers/pci/setup-bus.c | 24 ++++++++++---------
> 4 files changed, 33 insertions(+), 16 deletions(-)
>
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index a84a83f88..cfe8c2b67 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -3492,8 +3492,15 @@
> hpiosize=nn[KMG] The fixed amount of bus space which is
> reserved for hotplug bridge's IO window.
> Default size is 256 bytes.
> + hpmmiosize=nn[KMG] The fixed amount of bus space which is
> + reserved for hotplug bridge's MMIO window.
> + Default size is 2 megabytes.
> + hpmmioprefsize=nn[KMG] The fixed amount of bus space which is
> + reserved for hotplug bridge's MMIO_PREF window.
> + Default size is 2 megabytes.
> hpmemsize=nn[KMG] The fixed amount of bus space which is
> - reserved for hotplug bridge's memory window.
> + reserved for hotplug bridge's MMIO and
> + MMIO_PREF window.
> Default size is 2 megabytes.
> hpbussize=nn The minimum amount of additional bus numbers
> reserved for buses below a hotplug bridge.
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index a97e2571a..e0406c663 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -85,10 +85,12 @@ unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
> unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
>
> #define DEFAULT_HOTPLUG_IO_SIZE (256)
> -#define DEFAULT_HOTPLUG_MEM_SIZE (2*1024*1024)
> +#define DEFAULT_HOTPLUG_MMIO_SIZE (2*1024*1024)
> +#define DEFAULT_HOTPLUG_MMIO_PREF_SIZE (2*1024*1024)
> /* pci=hpmemsize=nnM,hpiosize=nn can override this */
> unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE;
> -unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
> +unsigned long pci_hotplug_mmio_size = DEFAULT_HOTPLUG_MMIO_SIZE;
> +unsigned long pci_hotplug_mmio_pref_size = DEFAULT_HOTPLUG_MMIO_PREF_SIZE;
>
> #define DEFAULT_HOTPLUG_BUS_SIZE 1
> unsigned long pci_hotplug_bus_size = DEFAULT_HOTPLUG_BUS_SIZE;
> @@ -6286,8 +6288,13 @@ static int __init pci_setup(char *str)
> pcie_ecrc_get_policy(str + 5);
> } else if (!strncmp(str, "hpiosize=", 9)) {
> pci_hotplug_io_size = memparse(str + 9, &str);
> + } else if (!strncmp(str, "hpmmiosize=", 11)) {
> + pci_hotplug_mmio_size = memparse(str + 11, &str);
> + } else if (!strncmp(str, "hpmmioprefsize=", 15)) {
> + pci_hotplug_mmio_pref_size = memparse(str + 15, &str);
> } else if (!strncmp(str, "hpmemsize=", 10)) {
> - pci_hotplug_mem_size = memparse(str + 10, &str);
> + pci_hotplug_mmio_size = memparse(str + 10, &str);
> + pci_hotplug_mmio_pref_size = pci_hotplug_mmio_size;
> } else if (!strncmp(str, "hpbussize=", 10)) {
> pci_hotplug_bus_size =
> simple_strtoul(str + 10, &str, 0);
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index 3f6947ee3..9faa55a15 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -218,7 +218,8 @@ extern const struct device_type pci_dev_type;
> extern const struct attribute_group *pci_bus_groups[];
>
> extern unsigned long pci_hotplug_io_size;
> -extern unsigned long pci_hotplug_mem_size;
> +extern unsigned long pci_hotplug_mmio_size;
> +extern unsigned long pci_hotplug_mmio_pref_size;
> extern unsigned long pci_hotplug_bus_size;
>
> /**
> diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
> index e7dbe2170..93fd2070a 100644
> --- a/drivers/pci/setup-bus.c
> +++ b/drivers/pci/setup-bus.c
> @@ -1178,7 +1178,8 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
> {
> struct pci_dev *dev;
> unsigned long mask, prefmask, type2 = 0, type3 = 0;
> - resource_size_t additional_mem_size = 0, additional_io_size = 0;
> + resource_size_t additional_io_size = 0, additional_mmio_size = 0,
> + additional_mmio_pref_size = 0;
> struct resource *b_res;
> int ret;
>
> @@ -1212,7 +1213,8 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
> pci_bridge_check_ranges(bus);
> if (bus->self->is_hotplug_bridge) {
> additional_io_size = pci_hotplug_io_size;
> - additional_mem_size = pci_hotplug_mem_size;
> + additional_mmio_size = pci_hotplug_mmio_size;
> + additional_mmio_pref_size = pci_hotplug_mmio_pref_size;
> }
> /* Fall through */
> default:
> @@ -1230,9 +1232,9 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
> if (b_res[2].flags & IORESOURCE_MEM_64) {
> prefmask |= IORESOURCE_MEM_64;
> ret = pbus_size_mem(bus, prefmask, prefmask,
> - prefmask, prefmask,
> - realloc_head ? 0 : additional_mem_size,
> - additional_mem_size, realloc_head);
> + prefmask, prefmask,
> + realloc_head ? 0 : additional_mmio_pref_size,
> + additional_mmio_pref_size, realloc_head);
>
> /*
> * If successful, all non-prefetchable resources
> @@ -1254,9 +1256,9 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
> if (!type2) {
> prefmask &= ~IORESOURCE_MEM_64;
> ret = pbus_size_mem(bus, prefmask, prefmask,
> - prefmask, prefmask,
> - realloc_head ? 0 : additional_mem_size,
> - additional_mem_size, realloc_head);
> + prefmask, prefmask,
> + realloc_head ? 0 : additional_mmio_pref_size,
> + additional_mmio_pref_size, realloc_head);
>
> /*
> * If successful, only non-prefetchable resources
> @@ -1265,7 +1267,7 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
> if (ret == 0)
> mask = prefmask;
> else
> - additional_mem_size += additional_mem_size;
> + additional_mmio_size += additional_mmio_pref_size;
>
> type2 = type3 = IORESOURCE_MEM;
> }
> @@ -1285,8 +1287,8 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
> * prefetchable resource in a 64-bit prefetchable window.
> */
> pbus_size_mem(bus, mask, IORESOURCE_MEM, type2, type3,
> - realloc_head ? 0 : additional_mem_size,
> - additional_mem_size, realloc_head);
> + realloc_head ? 0 : additional_mmio_size,
> + additional_mmio_size, realloc_head);
> break;
> }
> }
> --
> 2.23.0
>