[PATCH v4 02/13] iommu/amd: Prepare for generic IO page table framework

From: Suravee Suthikulpanit
Date: Tue Dec 15 2020 - 02:39:00 EST


Add initial hook up code to implement generic IO page table framework.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
drivers/iommu/amd/Kconfig | 1 +
drivers/iommu/amd/Makefile | 2 +-
drivers/iommu/amd/amd_iommu_types.h | 35 ++++++++++++++
drivers/iommu/amd/io_pgtable.c | 75 +++++++++++++++++++++++++++++
drivers/iommu/amd/iommu.c | 10 ----
drivers/iommu/io-pgtable.c | 3 ++
include/linux/io-pgtable.h | 2 +
7 files changed, 117 insertions(+), 11 deletions(-)
create mode 100644 drivers/iommu/amd/io_pgtable.c

diff --git a/drivers/iommu/amd/Kconfig b/drivers/iommu/amd/Kconfig
index 626b97d0dd21..a3cbafb603f5 100644
--- a/drivers/iommu/amd/Kconfig
+++ b/drivers/iommu/amd/Kconfig
@@ -10,6 +10,7 @@ config AMD_IOMMU
select IOMMU_API
select IOMMU_IOVA
select IOMMU_DMA
+ select IOMMU_IO_PGTABLE
depends on X86_64 && PCI && ACPI && HAVE_CMPXCHG_DOUBLE
help
With this option you can enable support for AMD IOMMU hardware in
diff --git a/drivers/iommu/amd/Makefile b/drivers/iommu/amd/Makefile
index dc5a2fa4fd37..a935f8f4b974 100644
--- a/drivers/iommu/amd/Makefile
+++ b/drivers/iommu/amd/Makefile
@@ -1,4 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
-obj-$(CONFIG_AMD_IOMMU) += iommu.o init.o quirks.o
+obj-$(CONFIG_AMD_IOMMU) += iommu.o init.o quirks.o io_pgtable.o
obj-$(CONFIG_AMD_IOMMU_DEBUGFS) += debugfs.o
obj-$(CONFIG_AMD_IOMMU_V2) += iommu_v2.o
diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h
index 494b42a31b7a..5d77f34e0fda 100644
--- a/drivers/iommu/amd/amd_iommu_types.h
+++ b/drivers/iommu/amd/amd_iommu_types.h
@@ -15,6 +15,7 @@
#include <linux/spinlock.h>
#include <linux/pci.h>
#include <linux/irqreturn.h>
+#include <linux/io-pgtable.h>

/*
* Maximum number of IOMMUs supported
@@ -252,6 +253,19 @@

#define GA_GUEST_NR 0x1

+#define IOMMU_IN_ADDR_BIT_SIZE 52
+#define IOMMU_OUT_ADDR_BIT_SIZE 52
+
+/*
+ * This bitmap is used to advertise the page sizes our hardware support
+ * to the IOMMU core, which will then use this information to split
+ * physically contiguous memory regions it is mapping into page sizes
+ * that we support.
+ *
+ * 512GB Pages are not supported due to a hardware bug
+ */
+#define AMD_IOMMU_PGSIZES ((~0xFFFUL) & ~(2ULL << 38))
+
/* Bit value definition for dte irq remapping fields*/
#define DTE_IRQ_PHYS_ADDR_MASK (((1ULL << 45)-1) << 6)
#define DTE_IRQ_REMAP_INTCTL_MASK (0x3ULL << 60)
@@ -465,6 +479,26 @@ struct amd_irte_ops;

#define AMD_IOMMU_FLAG_TRANS_PRE_ENABLED (1 << 0)

+#define io_pgtable_to_data(x) \
+ container_of((x), struct amd_io_pgtable, iop)
+
+#define io_pgtable_ops_to_data(x) \
+ io_pgtable_to_data(io_pgtable_ops_to_pgtable(x))
+
+#define io_pgtable_ops_to_domain(x) \
+ container_of(io_pgtable_ops_to_data(x), \
+ struct protection_domain, iop)
+
+#define io_pgtable_cfg_to_data(x) \
+ container_of((x), struct amd_io_pgtable, pgtbl_cfg)
+
+struct amd_io_pgtable {
+ struct io_pgtable_cfg pgtbl_cfg;
+ struct io_pgtable iop;
+ int mode;
+ u64 *root;
+};
+
/*
* This structure contains generic data for IOMMU protection domains
* independent of their use.
@@ -473,6 +507,7 @@ struct protection_domain {
struct list_head dev_list; /* List of all devices in this domain */
struct iommu_domain domain; /* generic domain handle used by
iommu core code */
+ struct amd_io_pgtable iop;
spinlock_t lock; /* mostly used to lock the page table*/
u16 id; /* the domain id written to the device table */
atomic64_t pt_root; /* pgtable root and pgtable mode */
diff --git a/drivers/iommu/amd/io_pgtable.c b/drivers/iommu/amd/io_pgtable.c
new file mode 100644
index 000000000000..aedf2c932c40
--- /dev/null
+++ b/drivers/iommu/amd/io_pgtable.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * CPU-agnostic AMD IO page table allocator.
+ *
+ * Copyright (C) 2020 Advanced Micro Devices, Inc.
+ * Author: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
+ */
+
+#define pr_fmt(fmt) "AMD-Vi: " fmt
+#define dev_fmt(fmt) pr_fmt(fmt)
+
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/io-pgtable.h>
+#include <linux/kernel.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/dma-mapping.h>
+
+#include <asm/barrier.h>
+
+#include "amd_iommu_types.h"
+#include "amd_iommu.h"
+
+static void v1_tlb_flush_all(void *cookie)
+{
+}
+
+static void v1_tlb_flush_walk(unsigned long iova, size_t size,
+ size_t granule, void *cookie)
+{
+}
+
+static void v1_tlb_flush_leaf(unsigned long iova, size_t size,
+ size_t granule, void *cookie)
+{
+}
+
+static void v1_tlb_add_page(struct iommu_iotlb_gather *gather,
+ unsigned long iova, size_t granule,
+ void *cookie)
+{
+}
+
+static const struct iommu_flush_ops v1_flush_ops = {
+ .tlb_flush_all = v1_tlb_flush_all,
+ .tlb_flush_walk = v1_tlb_flush_walk,
+ .tlb_flush_leaf = v1_tlb_flush_leaf,
+ .tlb_add_page = v1_tlb_add_page,
+};
+
+/*
+ * ----------------------------------------------------
+ */
+static void v1_free_pgtable(struct io_pgtable *iop)
+{
+}
+
+static struct io_pgtable *v1_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
+{
+ struct amd_io_pgtable *pgtable = io_pgtable_cfg_to_data(cfg);
+
+ cfg->pgsize_bitmap = AMD_IOMMU_PGSIZES,
+ cfg->ias = IOMMU_IN_ADDR_BIT_SIZE,
+ cfg->oas = IOMMU_OUT_ADDR_BIT_SIZE,
+ cfg->tlb = &v1_flush_ops;
+
+ return &pgtable->iop;
+}
+
+struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns = {
+ .alloc = v1_alloc_pgtable,
+ .free = v1_free_pgtable,
+};
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 7f6b0f60b958..45d3977d6c00 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -58,16 +58,6 @@
#define HT_RANGE_START (0xfd00000000ULL)
#define HT_RANGE_END (0xffffffffffULL)

-/*
- * This bitmap is used to advertise the page sizes our hardware support
- * to the IOMMU core, which will then use this information to split
- * physically contiguous memory regions it is mapping into page sizes
- * that we support.
- *
- * 512GB Pages are not supported due to a hardware bug
- */
-#define AMD_IOMMU_PGSIZES ((~0xFFFUL) & ~(2ULL << 38))
-
#define DEFAULT_PGTABLE_LEVEL PAGE_MODE_3_LEVEL

static DEFINE_SPINLOCK(pd_bitmap_lock);
diff --git a/drivers/iommu/io-pgtable.c b/drivers/iommu/io-pgtable.c
index 94394c81468f..6e9917ce980f 100644
--- a/drivers/iommu/io-pgtable.c
+++ b/drivers/iommu/io-pgtable.c
@@ -24,6 +24,9 @@ io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] = {
#ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S
[ARM_V7S] = &io_pgtable_arm_v7s_init_fns,
#endif
+#ifdef CONFIG_AMD_IOMMU
+ [AMD_IOMMU_V1] = &io_pgtable_amd_iommu_v1_init_fns,
+#endif
};

struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h
index 4cde111e425b..c9794671dccc 100644
--- a/include/linux/io-pgtable.h
+++ b/include/linux/io-pgtable.h
@@ -15,6 +15,7 @@ enum io_pgtable_fmt {
ARM_64_LPAE_S2,
ARM_V7S,
ARM_MALI_LPAE,
+ AMD_IOMMU_V1,
IO_PGTABLE_NUM_FMTS,
};

@@ -254,5 +255,6 @@ extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
+extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns;

#endif /* __IO_PGTABLE_H */
--
2.17.1