forked from pool/grub2
47 lines
1.6 KiB
Diff
47 lines
1.6 KiB
Diff
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From 2f06e09673e48f6a91486a8ad38f45c160d537fe Mon Sep 17 00:00:00 2001
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From: "mike.travis@hpe.com" <mike.travis@hpe.com>
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Date: Wed, 28 Mar 2018 11:42:18 -0500
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Subject: Fix PCIe LER when GRUB2 accesses non-enabled MMIO data from VGA
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A GPU inserted into a PCIe I/O slot disappears during system startup.
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The problem centers around GRUB and a specific VGA init function in
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efi_uga.c. This causes an LER (link error recorvery) because the MMIO
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memory has not been enabled before attempting access.
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The fix is to add the same coding used in other VGA drivers, specifically
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to add a check to insure that it is indeed a VGA controller. And then
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enable the MMIO address space with the specific bits.
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Signed-off-by: Mike Travis <mike.travis@hpe.com>
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---
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grub-core/video/efi_uga.c | 11 ++++++++++-
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1 file changed, 10 insertions(+), 1 deletion(-)
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diff --git a/grub-core/video/efi_uga.c b/grub-core/video/efi_uga.c
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index 464ede874..32ef7efbc 100644
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--- a/grub-core/video/efi_uga.c
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+++ b/grub-core/video/efi_uga.c
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@@ -95,9 +95,18 @@ find_card (grub_pci_device_t dev, grub_pci_id_t pciid, void *data)
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{
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struct find_framebuf_ctx *ctx = data;
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grub_pci_address_t addr;
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+ grub_pci_address_t rcaddr;
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+ grub_uint32_t subclass;
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addr = grub_pci_make_address (dev, GRUB_PCI_REG_CLASS);
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- if (grub_pci_read (addr) >> 24 == 0x3)
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+ subclass = (grub_pci_read (addr) >> 16) & 0xffff;
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+ if (subclass != GRUB_PCI_CLASS_SUBCLASS_VGA)
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+ return 0;
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+
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+ /* Enable MEM address spaces */
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+ rcaddr = grub_pci_make_address (dev, GRUB_PCI_REG_COMMAND);
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+ grub_pci_write_word (rcaddr, grub_pci_read_word (rcaddr) | GRUB_PCI_COMMAND_MEM_ENABLED);
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+
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{
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int i;
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--
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2.13.6
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