[Devel] [PATCH v9 0/3] Cavium ThunderX2 SMMUv3 errata workarounds

[Robert Richter]

On 22.06.17 19:58:22, Will Deacon wrote:
> On Thu, Jun 22, 2017 at 07:22:57PM +0100, Will Deacon wrote:
> > On Thu, Jun 22, 2017 at 05:35:35PM +0530, Geetha sowjanya wrote:
> > > Cavium ThunderX2 SMMUv3 implementation has two Silicon Erratas.
> > > 1. Errata ID #74
> > >    SMMU register alias Page 1 is not implemented
> > > 2. Errata ID #126
> > >    SMMU doesnt support unique IRQ lines and also MSI for gerror,
> > >    eventq and cmdq-sync
> > > 
> > > The following patchset does software workaround for these two erratas.
> > 
> > I've picked up the first two patches, and left comments on the final patch.
> 
> ... except that it doesn't build:
> 
> 
> drivers/acpi/arm64/iort.c: In function ‘arm_smmu_v3_resource_size’:
> drivers/acpi/arm64/iort.c:837:21: error: ‘ACPI_IORT_SMMU_V3_CAVIUM_CN99XX’ undeclared (first use in this function)
>   if (smmu->model == ACPI_IORT_SMMU_V3_CAVIUM_CN99XX)
>                      ^
> drivers/acpi/arm64/iort.c:837:21: note: each undeclared identifier is reported only once for each function it appears in
> make[4]: *** [drivers/acpi/arm64/iort.o] Error 1
> 
> 
> I don't see ACPI_IORT_SMMU_V3_CAVIUM_CN99XX defined, even in linux-next.
> 
> What's the plan here?

It is defined already in acpica and we actually waiting for the acpi
maintainers to include it:

 https://github.com/acpica/acpica/commit/d00a4eb86e64

We could add

/* Until ACPICA headers cover IORT rev. C */
#ifndef ACPI_IORT_SMMU_V3_CAVIUM_CN99XX
#define ACPI_IORT_SMMU_V3_CAVIUM_CN99XX		0x2
#endif

to both files:

 drivers/acpi/arm64/iort.c
 drivers/iommu/arm-smmu-v3.c

This is similar to what Robin did.

(I checked arm64 include files and the closest was
arch/arm64/include/asm/acpi.h, bug this seems not really suitable to
me.)

I have created a separate patch to be applied at first below. We can
revert it after acpica was updated.

-Robert




>From ad7f0112a2a71059c32bd315835c33cc7bc660b8 Mon Sep 17 00:00:00 2001
From: Robert Richter <rrichter at cavium.com>
Date: Thu, 22 Jun 2017 21:20:54 +0200
Subject: [PATCH] iommu/arm-smmu-v3: Add temporary Cavium SMMU-V3 model nuber
 definitions

The model number is already defined in acpica and we actually waiting
for the acpi maintainers to include it:

 https://github.com/acpica/acpica/commit/d00a4eb86e64

Adding those temporary definitions until the change makes it into
include/acpi/actbl2.h.

Signed-off-by: Robert Richter <rrichter at cavium.com>
---
 drivers/acpi/arm64/iort.c   | 5 +++++
 drivers/iommu/arm-smmu-v3.c | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 797b28dc7b34..15491237a657 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -31,6 +31,11 @@
 #define IORT_IOMMU_TYPE		((1 << ACPI_IORT_NODE_SMMU) |	\
 				(1 << ACPI_IORT_NODE_SMMU_V3))
 
+/* Until ACPICA headers cover IORT rev. C */
+#ifndef ACPI_IORT_SMMU_V3_CAVIUM_CN99XX
+#define ACPI_IORT_SMMU_V3_CAVIUM_CN99XX		0x2
+#endif
+
 struct iort_its_msi_chip {
 	struct list_head	list;
 	struct fwnode_handle	*fw_node;
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 380969aa60d5..c759dfa7442d 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -412,6 +412,11 @@
 #define MSI_IOVA_BASE			0x8000000
 #define MSI_IOVA_LENGTH			0x100000
 
+/* Until ACPICA headers cover IORT rev. C */
+#ifndef ACPI_IORT_SMMU_V3_CAVIUM_CN99XX
+#define ACPI_IORT_SMMU_V3_CAVIUM_CN99XX		0x2
+#endif
+
 static bool disable_bypass;
 module_param_named(disable_bypass, disable_bypass, bool, S_IRUGO);
 MODULE_PARM_DESC(disable_bypass,
-- 
2.11.0