Revert "PCI: loongson: Prevent LS7A MRRS increases"

This reverts commit d8c911d3d8.

It breaks the ABI right now, but will be brought back at the next ABI
break as it will be needed for Android systems.

Bug: 161946584
Change-Id: I8543def5fb03133f4772ba1976f882d182bba677
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
This commit is contained in:
Greg Kroah-Hartman
2023-03-16 18:22:11 +00:00
committed by Matthias Männich
parent 8c8619f60e
commit 1a291b98a3
3 changed files with 28 additions and 25 deletions

View File

@@ -75,23 +75,37 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_LS7A_LPC, system_bus_quirk);
static void loongson_mrrs_quirk(struct pci_dev *pdev)
static void loongson_mrrs_quirk(struct pci_dev *dev)
{
/*
* Some Loongson PCIe ports have h/w limitations of maximum read
* request size. They can't handle anything larger than this. So
* force this limit on any devices attached under these ports.
*/
struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
struct pci_bus *bus = dev->bus;
struct pci_dev *bridge;
static const struct pci_device_id bridge_devids[] = {
{ PCI_VDEVICE(LOONGSON, DEV_PCIE_PORT_0) },
{ PCI_VDEVICE(LOONGSON, DEV_PCIE_PORT_1) },
{ PCI_VDEVICE(LOONGSON, DEV_PCIE_PORT_2) },
{ 0, },
};
bridge->no_inc_mrrs = 1;
/* look for the matching bridge */
while (!pci_is_root_bus(bus)) {
bridge = bus->self;
bus = bus->parent;
/*
* Some Loongson PCIe ports have a h/w limitation of
* 256 bytes maximum read request size. They can't handle
* anything larger than this. So force this limit on
* any devices attached under these ports.
*/
if (pci_match_id(bridge_devids, bridge)) {
if (pcie_get_readrq(dev) > 256) {
pci_info(dev, "limiting MRRS to 256\n");
pcie_set_readrq(dev, 256);
}
break;
}
}
}
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_PCIE_PORT_0, loongson_mrrs_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_PCIE_PORT_1, loongson_mrrs_quirk);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
DEV_PCIE_PORT_2, loongson_mrrs_quirk);
DECLARE_PCI_FIXUP_ENABLE(PCI_ANY_ID, PCI_ANY_ID, loongson_mrrs_quirk);
static void loongson_pci_pin_quirk(struct pci_dev *pdev)
{

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@@ -6017,7 +6017,6 @@ int pcie_set_readrq(struct pci_dev *dev, int rq)
{
u16 v;
int ret;
struct pci_host_bridge *bridge = pci_find_host_bridge(dev->bus);
if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
return -EINVAL;
@@ -6036,15 +6035,6 @@ int pcie_set_readrq(struct pci_dev *dev, int rq)
v = (ffs(rq) - 8) << 12;
if (bridge->no_inc_mrrs) {
int max_mrrs = pcie_get_readrq(dev);
if (rq > max_mrrs) {
pci_info(dev, "can't set Max_Read_Request_Size to %d; max is %d\n", rq, max_mrrs);
return -EINVAL;
}
}
ret = pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
PCI_EXP_DEVCTL_READRQ, v);

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@@ -570,7 +570,6 @@ struct pci_host_bridge {
void *release_data;
unsigned int ignore_reset_delay:1; /* For entire hierarchy */
unsigned int no_ext_tags:1; /* No Extended Tags */
unsigned int no_inc_mrrs:1; /* No Increase MRRS */
unsigned int native_aer:1; /* OS may use PCIe AER */
unsigned int native_pcie_hotplug:1; /* OS may use PCIe hotplug */
unsigned int native_shpc_hotplug:1; /* OS may use SHPC hotplug */