Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/drivers/firmware/efi/libstub/pci.c b/drivers/firmware/efi/libstub/pci.c
new file mode 100644
index 0000000..99fb25d
--- /dev/null
+++ b/drivers/firmware/efi/libstub/pci.c
@@ -0,0 +1,114 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCI-related functions used by the EFI stub on multiple
+ * architectures.
+ *
+ * Copyright 2019 Google, LLC
+ */
+
+#include <linux/efi.h>
+#include <linux/pci.h>
+
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+void efi_pci_disable_bridge_busmaster(void)
+{
+ efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID;
+ unsigned long pci_handle_size = 0;
+ efi_handle_t *pci_handle = NULL;
+ efi_handle_t handle;
+ efi_status_t status;
+ u16 class, command;
+ int i;
+
+ status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, &pci_proto,
+ NULL, &pci_handle_size, NULL);
+
+ if (status != EFI_BUFFER_TOO_SMALL) {
+ if (status != EFI_SUCCESS && status != EFI_NOT_FOUND)
+ efi_err("Failed to locate PCI I/O handles'\n");
+ return;
+ }
+
+ status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, pci_handle_size,
+ (void **)&pci_handle);
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to allocate memory for 'pci_handle'\n");
+ return;
+ }
+
+ status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, &pci_proto,
+ NULL, &pci_handle_size, pci_handle);
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to locate PCI I/O handles'\n");
+ goto free_handle;
+ }
+
+ for_each_efi_handle(handle, pci_handle, pci_handle_size, i) {
+ efi_pci_io_protocol_t *pci;
+ unsigned long segment_nr, bus_nr, device_nr, func_nr;
+
+ status = efi_bs_call(handle_protocol, handle, &pci_proto,
+ (void **)&pci);
+ if (status != EFI_SUCCESS)
+ continue;
+
+ /*
+ * Disregard devices living on bus 0 - these are not behind a
+ * bridge so no point in disconnecting them from their drivers.
+ */
+ status = efi_call_proto(pci, get_location, &segment_nr, &bus_nr,
+ &device_nr, &func_nr);
+ if (status != EFI_SUCCESS || bus_nr == 0)
+ continue;
+
+ /*
+ * Don't disconnect VGA controllers so we don't risk losing
+ * access to the framebuffer. Drivers for true PCIe graphics
+ * controllers that are behind a PCIe root port do not use
+ * DMA to implement the GOP framebuffer anyway [although they
+ * may use it in their implementation of Gop->Blt()], and so
+ * disabling DMA in the PCI bridge should not interfere with
+ * normal operation of the device.
+ */
+ status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
+ PCI_CLASS_DEVICE, 1, &class);
+ if (status != EFI_SUCCESS || class == PCI_CLASS_DISPLAY_VGA)
+ continue;
+
+ /* Disconnect this handle from all its drivers */
+ efi_bs_call(disconnect_controller, handle, NULL, NULL);
+ }
+
+ for_each_efi_handle(handle, pci_handle, pci_handle_size, i) {
+ efi_pci_io_protocol_t *pci;
+
+ status = efi_bs_call(handle_protocol, handle, &pci_proto,
+ (void **)&pci);
+ if (status != EFI_SUCCESS || !pci)
+ continue;
+
+ status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
+ PCI_CLASS_DEVICE, 1, &class);
+
+ if (status != EFI_SUCCESS || class != PCI_CLASS_BRIDGE_PCI)
+ continue;
+
+ /* Disable busmastering */
+ status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
+ PCI_COMMAND, 1, &command);
+ if (status != EFI_SUCCESS || !(command & PCI_COMMAND_MASTER))
+ continue;
+
+ command &= ~PCI_COMMAND_MASTER;
+ status = efi_call_proto(pci, pci.write, EfiPciIoWidthUint16,
+ PCI_COMMAND, 1, &command);
+ if (status != EFI_SUCCESS)
+ efi_err("Failed to disable PCI busmastering\n");
+ }
+
+free_handle:
+ efi_bs_call(free_pool, pci_handle);
+}