firmware/br-ext-chip-allwinner/board/v83x/kernel/patches/00000-arch_arm64_kernel_pci...

100 lines
3.0 KiB
Diff

diff -drupN a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
--- a/arch/arm64/kernel/pci.c 2018-08-06 17:23:04.000000000 +0300
+++ b/arch/arm64/kernel/pci.c 2022-06-12 05:28:14.000000000 +0300
@@ -23,11 +23,94 @@
#include <linux/slab.h>
/*
+ * If the bus contains any of these devices, then we must not turn on
+ * parity checking of any kind. Currently this is CyberPro 20x0 only.
+ */
+static inline int pdev_bad_for_parity(struct pci_dev *dev)
+{
+ return ((dev->vendor == PCI_VENDOR_ID_INTERG &&
+ (dev->device == PCI_DEVICE_ID_INTERG_2000 ||
+ dev->device == PCI_DEVICE_ID_INTERG_2010)) ||
+ (dev->vendor == PCI_VENDOR_ID_ITE &&
+ dev->device == PCI_DEVICE_ID_ITE_8152));
+
+}
+
+/*
* Called after each bus is probed, but before its children are examined
*/
void pcibios_fixup_bus(struct pci_bus *bus)
{
- /* nothing to do, expected to be removed in the future */
+ struct pci_dev *dev;
+ u16 features = PCI_COMMAND_SERR | PCI_COMMAND_PARITY | PCI_COMMAND_FAST_BACK;
+
+ /*
+ * Walk the devices on this bus, working out what we can
+ * and can't support.
+ */
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ u16 status;
+
+ pci_read_config_word(dev, PCI_STATUS, &status);
+
+ /*
+ * If any device on this bus does not support fast back
+ * to back transfers, then the bus as a whole is not able
+ * to support them. Having fast back to back transfers
+ * on saves us one PCI cycle per transaction.
+ */
+ if (!(status & PCI_STATUS_FAST_BACK))
+ features &= ~PCI_COMMAND_FAST_BACK;
+
+ if (pdev_bad_for_parity(dev))
+ features &= ~(PCI_COMMAND_SERR | PCI_COMMAND_PARITY);
+
+ switch (dev->class >> 8) {
+ case PCI_CLASS_BRIDGE_PCI:
+ pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &status);
+ status |= PCI_BRIDGE_CTL_PARITY|PCI_BRIDGE_CTL_MASTER_ABORT;
+ status &= ~(PCI_BRIDGE_CTL_BUS_RESET|PCI_BRIDGE_CTL_FAST_BACK);
+ pci_write_config_word(dev, PCI_BRIDGE_CONTROL, status);
+ break;
+
+ case PCI_CLASS_BRIDGE_CARDBUS:
+ pci_read_config_word(dev, PCI_CB_BRIDGE_CONTROL, &status);
+ status |= PCI_CB_BRIDGE_CTL_PARITY|PCI_CB_BRIDGE_CTL_MASTER_ABORT;
+ pci_write_config_word(dev, PCI_CB_BRIDGE_CONTROL, status);
+ break;
+ }
+ }
+
+ /*
+ * Now walk the devices again, this time setting them up.
+ */
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ u16 cmd;
+
+ pci_read_config_word(dev, PCI_COMMAND, &cmd);
+ cmd |= features;
+ pci_write_config_word(dev, PCI_COMMAND, cmd);
+
+ pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE,
+ L1_CACHE_BYTES >> 2);
+ }
+
+ /*
+ * Propagate the flags to the PCI bridge.
+ */
+ if (bus->self && bus->self->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
+ if (features & PCI_COMMAND_FAST_BACK)
+ bus->bridge_ctl |= PCI_BRIDGE_CTL_FAST_BACK;
+ if (features & PCI_COMMAND_PARITY)
+ bus->bridge_ctl |= PCI_BRIDGE_CTL_PARITY;
+ }
+
+ /*
+ * Report what we did for this bus
+ */
+ pr_info("PCI: bus%d: Fast back to back transfers %sabled\n",
+ bus->number, (features & PCI_COMMAND_FAST_BACK) ? "en" : "dis");
+
}
/*