aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorAlexey Kardashevskiy <aik@ozlabs.ru>2019-05-07 16:25:59 +1000
committerMichael Ellerman <mpe@ellerman.id.au>2019-07-03 15:19:35 +1000
commit1a047cc7e53cb10e4706c09f6e92b2fa911a2bf2 (patch)
treef7ec84bc255ca2d4e135f52540851d429d2573e4
parentpowerpc/pseries/dma: Allow SWIOTLB (diff)
downloadlinux-dev-1a047cc7e53cb10e4706c09f6e92b2fa911a2bf2.tar.xz
linux-dev-1a047cc7e53cb10e4706c09f6e92b2fa911a2bf2.zip
powerpc/pseries/dma: Enable SWIOTLB
So far the pseries platforms has always been using IOMMU making SWIOTLB unnecessary. Now we want secure guests which means devices can only access certain areas of guest physical memory; we are going to use SWIOTLB for this purpose. This allows SWIOTLB for pseries. By default there is no change in behavior. This enables SWIOTLB when the "swiotlb" kernel parameter is set to "force". With the SWIOTLB enabled, the kernel creates a directly mapped DMA window (using the usual DDW mechanism) and implements SWIOTLB on top of that. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
-rw-r--r--arch/powerpc/platforms/pseries/Kconfig1
-rw-r--r--arch/powerpc/platforms/pseries/setup.c5
2 files changed, 6 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index 9c6b3d860518..b9e8b608de01 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -23,6 +23,7 @@ config PPC_PSERIES
select ARCH_RANDOM
select PPC_DOORBELL
select FORCE_SMP
+ select SWIOTLB
default y
config PPC_SPLPAR
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index e4f0dfd4ae33..30d72b587ac5 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -42,6 +42,7 @@
#include <linux/of.h>
#include <linux/of_pci.h>
#include <linux/memblock.h>
+#include <linux/swiotlb.h>
#include <asm/mmu.h>
#include <asm/processor.h>
@@ -71,6 +72,7 @@
#include <asm/isa-bridge.h>
#include <asm/security_features.h>
#include <asm/asm-const.h>
+#include <asm/swiotlb.h>
#include "pseries.h"
#include "../../../../drivers/pci/pci.h"
@@ -797,6 +799,9 @@ static void __init pSeries_setup_arch(void)
}
ppc_md.pcibios_root_bridge_prepare = pseries_root_bridge_prepare;
+
+ if (swiotlb_force == SWIOTLB_FORCE)
+ ppc_swiotlb_enable = 1;
}
static void pseries_panic(char *str)