The patch titled
Intel IOMMU: Iommu Gfx workaround
has been added to the -mm tree. Its filename is
intel-iommu-iommu-gfx-workaround.patch
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: Intel IOMMU: Iommu Gfx workaround
From: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@xxxxxxxxx>
When we fix all the opensource gfx drivers to use the DMA api's, at that time
we can yank this config options out.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Muli Ben-Yehuda <muli@xxxxxxxxxx>
Cc: "Siddha, Suresh B" <suresh.b.siddha@xxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxx>
Cc: Ashok Raj <ashok.raj@xxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Christoph Lameter <clameter@xxxxxxx>
Cc: Greg KH <greg@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/Intel-IOMMU.txt | 5 ++++
arch/x86_64/Kconfig | 11 ++++++++++
arch/x86_64/kernel/e820.c | 19 ++++++++++++++++++
drivers/pci/intel-iommu.c | 33 ++++++++++++++++++++++++++++++++
drivers/pci/intel-iommu.h | 7 ++++++
5 files changed, 75 insertions(+)
diff -puN Documentation/Intel-IOMMU.txt~intel-iommu-iommu-gfx-workaround Documentation/Intel-IOMMU.txt
--- a/Documentation/Intel-IOMMU.txt~intel-iommu-iommu-gfx-workaround
+++ a/Documentation/Intel-IOMMU.txt
@@ -57,6 +57,11 @@ Graphics Problems?
If you encounter issues with graphics devices, you can try adding
option intel_iommu=igfx_off to turn off the integrated graphics engine.
+If it happens to be a PCI device included in the INCLUDE_ALL Engine,
+then try enabling CONFIG_DMAR_GFX_WA to setup a 1-1 map. We hear
+graphics drivers may be in process of using DMA api's in the near
+future and at that time this option can be yanked out.
+
Some exceptions to IOVA
-----------------------
Interrupt ranges are not address translated, (0xfee00000 - 0xfeefffff).
diff -puN arch/x86_64/Kconfig~intel-iommu-iommu-gfx-workaround arch/x86_64/Kconfig
--- a/arch/x86_64/Kconfig~intel-iommu-iommu-gfx-workaround
+++ a/arch/x86_64/Kconfig
@@ -759,6 +759,17 @@ config DMAR
and includes pci device scope covered by these DMA
remapping device.
+config DMAR_GFX_WA
+ bool "Support for Graphics workaround"
+ depends on DMAR
+ default y
+ help
+ Current Graphics drivers tend to use physical address
+ for DMA and avoid using DMA api's. Setting this config
+ option permits the IOMMU driver to set a unity map for
+ all the OS visible memory. Hence the driver can continue
+ to use physical addresses for DMA.
+
source "drivers/pci/pcie/Kconfig"
source "drivers/pci/Kconfig"
diff -puN arch/x86_64/kernel/e820.c~intel-iommu-iommu-gfx-workaround arch/x86_64/kernel/e820.c
--- a/arch/x86_64/kernel/e820.c~intel-iommu-iommu-gfx-workaround
+++ a/arch/x86_64/kernel/e820.c
@@ -723,3 +723,22 @@ __init void e820_setup_gap(void)
printk(KERN_INFO "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
pci_mem_start, gapstart, gapsize);
}
+
+int __init arch_get_ram_range(int slot, u64 *addr, u64 *size)
+{
+ int i;
+
+ if (slot < 0 || slot >= e820.nr_map)
+ return -1;
+ for (i = slot; i < e820.nr_map; i++) {
+ if (e820.map[i].type != E820_RAM)
+ continue;
+ break;
+ }
+ if (i == e820.nr_map || e820.map[i].addr > (max_pfn << PAGE_SHIFT))
+ return -1;
+ *addr = e820.map[i].addr;
+ *size = min_t(u64, e820.map[i].size + e820.map[i].addr,
+ max_pfn << PAGE_SHIFT) - *addr;
+ return i + 1;
+}
diff -puN drivers/pci/intel-iommu.c~intel-iommu-iommu-gfx-workaround drivers/pci/intel-iommu.c
--- a/drivers/pci/intel-iommu.c~intel-iommu-iommu-gfx-workaround
+++ a/drivers/pci/intel-iommu.c
@@ -1601,6 +1601,36 @@ static inline int iommu_prepare_rmrr_dev
rmrr->end_address + 1);
}
+#ifdef CONFIG_DMAR_GFX_WA
+extern int arch_get_ram_range(int slot, u64 *addr, u64 *size);
+static void __init iommu_prepare_gfx_mapping(void)
+{
+ struct pci_dev *pdev = NULL;
+ u64 base, size;
+ int slot;
+ int ret;
+
+ for_each_pci_dev(pdev) {
+ if (pdev->sysdata == DUMMY_DEVICE_DOMAIN_INFO ||
+ !IS_GFX_DEVICE(pdev))
+ continue;
+ printk(KERN_INFO "IOMMU: gfx device %s 1-1 mapping\n",
+ pci_name(pdev));
+ slot = arch_get_ram_range(0, &base, &size);
+ while (slot >= 0) {
+ ret = iommu_prepare_identity_map(pdev,
+ base, base + size);
+ if (ret)
+ goto error;
+ slot = arch_get_ram_range(slot, &base, &size);
+ }
+ continue;
+error:
+ printk(KERN_ERR "IOMMU: mapping reserved region failed\n");
+ }
+}
+#endif
+
int __init init_dmars(void)
{
struct dmar_drhd_unit *drhd;
@@ -1664,6 +1694,8 @@ int __init init_dmars(void)
}
}
+ iommu_prepare_gfx_mapping();
+
/*
* for each drhd
* enable fault log
@@ -2175,3 +2207,4 @@ int __init intel_iommu_init(void)
dma_ops = &intel_dma_ops;
return 0;
}
+
diff -puN drivers/pci/intel-iommu.h~intel-iommu-iommu-gfx-workaround drivers/pci/intel-iommu.h
--- a/drivers/pci/intel-iommu.h~intel-iommu-iommu-gfx-workaround
+++ a/drivers/pci/intel-iommu.h
@@ -315,4 +315,11 @@ struct intel_iommu {
struct sys_device sysdev;
};
+#ifndef CONFIG_DMAR_GFX_WA
+static inline void iommu_prepare_gfx_mapping(void)
+{
+ return;
+}
+#endif /* !CONFIG_DMAR_GFX_WA */
+
#endif
_
Patches currently in -mm which might be from anil.s.keshavamurthy@xxxxxxxxx are
jprobes-make-struct-jprobeentry-a-void.patch
jprobes-remove-jprobe_entry.patch
jprobes-make-jprobes-a-little-safer-for-users.patch
jprobes-make-jprobes-a-little-safer-for-users-fix.patch
intel-iommu-dmar-detection-and-parsing-logic.patch
intel-iommu-pci-generic-helper-function.patch
intel-iommu-pci-generic-helper-function-fix.patch
intel-iommu-clflush_cache_range-now-takes-size-param.patch
intel-iommu-iova-allocation-and-management-routines.patch
intel-iommu-iova-allocation-and-management-routines-fix.patch
intel-iommu-intel-iommu-driver.patch
intel-iommu-intel-iommu-driver-fix.patch
intel-iommu-avoid-memory-allocation-failures-in-dma-map-api-calls.patch
intel-iommu-intel-iommu-cmdline-option-forcedac.patch
intel-iommu-dmar-fault-handling-support.patch
intel-iommu-iommu-gfx-workaround.patch
intel-iommu-iommu-floppy-workaround.patch
intel-iommu-iommu-floppy-workaround-fix.patch
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