Merge branch 'for-joerg/io-pgtable' of...

Merge branch 'for-joerg/io-pgtable' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into arm/io-pgtable

MAINTAINERS

@@ -1793,11 +1793,13 @@ F:	drivers/edac/synopsys_edac.c
 
 ARM SMMU DRIVERS
 M:	Will Deacon <will.deacon@arm.com>
+R:	Robin Murphy <robin.murphy@arm.com>
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 S:	Maintained
 F:	drivers/iommu/arm-smmu.c
 F:	drivers/iommu/arm-smmu-v3.c
 F:	drivers/iommu/io-pgtable-arm.c
+F:	drivers/iommu/io-pgtable-arm-v7s.c
 
 ARM64 PORT (AARCH64 ARCHITECTURE)
 M:	Catalin Marinas <catalin.marinas@arm.com>

drivers/iommu/Kconfig

@@ -39,6 +39,25 @@ config IOMMU_IO_PGTABLE_LPAE_SELFTEST
 
 	  If unsure, say N here.
 
+config IOMMU_IO_PGTABLE_ARMV7S
+	bool "ARMv7/v8 Short Descriptor Format"
+	select IOMMU_IO_PGTABLE
+	depends on HAS_DMA && (ARM || ARM64 || COMPILE_TEST)
+	help
+	  Enable support for the ARM Short-descriptor pagetable format.
+	  This supports 32-bit virtual and physical addresses mapped using
+	  2-level tables with 4KB pages/1MB sections, and contiguous entries
+	  for 64KB pages/16MB supersections if indicated by the IOMMU driver.
+
+config IOMMU_IO_PGTABLE_ARMV7S_SELFTEST
+	bool "ARMv7s selftests"
+	depends on IOMMU_IO_PGTABLE_ARMV7S
+	help
+	  Enable self-tests for ARMv7s page table allocator. This performs
+	  a series of page-table consistency checks during boot.
+
+	  If unsure, say N here.
+
 endmenu
 
 config IOMMU_IOVA

drivers/iommu/Makefile

@@ -3,6 +3,7 @@ obj-$(CONFIG_IOMMU_API) += iommu-traces.o
 obj-$(CONFIG_IOMMU_API) += iommu-sysfs.o
 obj-$(CONFIG_IOMMU_DMA) += dma-iommu.o
 obj-$(CONFIG_IOMMU_IO_PGTABLE) += io-pgtable.o
+obj-$(CONFIG_IOMMU_IO_PGTABLE_ARMV7S) += io-pgtable-arm-v7s.o
 obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE) += io-pgtable-arm.o
 obj-$(CONFIG_IOMMU_IOVA) += iova.o
 obj-$(CONFIG_OF_IOMMU)	+= of_iommu.o

drivers/iommu/io-pgtable-arm.c

@@ -446,7 +446,6 @@ static int arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
 	unsigned long blk_start, blk_end;
 	phys_addr_t blk_paddr;
 	arm_lpae_iopte table = 0;
-	struct io_pgtable_cfg *cfg = &data->iop.cfg;
 
 	blk_start = iova & ~(blk_size - 1);
 	blk_end = blk_start + blk_size;
@@ -472,9 +471,9 @@ static int arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
 		}
 	}
 
-	__arm_lpae_set_pte(ptep, table, cfg);
+	__arm_lpae_set_pte(ptep, table, &data->iop.cfg);
 	iova &= ~(blk_size - 1);
-	cfg->tlb->tlb_add_flush(iova, blk_size, blk_size, true, data->iop.cookie);
+	io_pgtable_tlb_add_flush(&data->iop, iova, blk_size, blk_size, true);
 	return size;
 }
 
@@ -483,8 +482,7 @@ static int __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
 			    arm_lpae_iopte *ptep)
 {
 	arm_lpae_iopte pte;
-	const struct iommu_gather_ops *tlb = data->iop.cfg.tlb;
-	void *cookie = data->iop.cookie;
+	struct io_pgtable *iop = &data->iop;
 	size_t blk_size = ARM_LPAE_BLOCK_SIZE(lvl, data);
 
 	/* Something went horribly wrong and we ran out of page table */
@@ -498,17 +496,17 @@ static int __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
 
 	/* If the size matches this level, we're in the right place */
 	if (size == blk_size) {
-		__arm_lpae_set_pte(ptep, 0, &data->iop.cfg);
+		__arm_lpae_set_pte(ptep, 0, &iop->cfg);
 
 		if (!iopte_leaf(pte, lvl)) {
 			/* Also flush any partial walks */
-			tlb->tlb_add_flush(iova, size, ARM_LPAE_GRANULE(data),
-					   false, cookie);
-			tlb->tlb_sync(cookie);
+			io_pgtable_tlb_add_flush(iop, iova, size,
+						ARM_LPAE_GRANULE(data), false);
+			io_pgtable_tlb_sync(iop);
 			ptep = iopte_deref(pte, data);
 			__arm_lpae_free_pgtable(data, lvl + 1, ptep);
 		} else {
-			tlb->tlb_add_flush(iova, size, size, true, cookie);
+			io_pgtable_tlb_add_flush(iop, iova, size, size, true);
 		}
 
 		return size;
@@ -532,13 +530,12 @@ static int arm_lpae_unmap(struct io_pgtable_ops *ops, unsigned long iova,
 {
 	size_t unmapped;
 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
-	struct io_pgtable *iop = &data->iop;
 	arm_lpae_iopte *ptep = data->pgd;
 	int lvl = ARM_LPAE_START_LVL(data);
 
 	unmapped = __arm_lpae_unmap(data, iova, size, lvl, ptep);
 	if (unmapped)
-		iop->cfg.tlb->tlb_sync(iop->cookie);
+		io_pgtable_tlb_sync(&data->iop);
 
 	return unmapped;
 }
@@ -662,8 +659,12 @@ static struct io_pgtable *
 arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
 {
 	u64 reg;
-	struct arm_lpae_io_pgtable *data = arm_lpae_alloc_pgtable(cfg);
+	struct arm_lpae_io_pgtable *data;
 
+	if (cfg->quirks & ~IO_PGTABLE_QUIRK_ARM_NS)
+		return NULL;
+
+	data = arm_lpae_alloc_pgtable(cfg);
 	if (!data)
 		return NULL;
 
@@ -746,8 +747,13 @@ static struct io_pgtable *
 arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
 {
 	u64 reg, sl;
-	struct arm_lpae_io_pgtable *data = arm_lpae_alloc_pgtable(cfg);
+	struct arm_lpae_io_pgtable *data;
+
+	/* The NS quirk doesn't apply at stage 2 */
+	if (cfg->quirks)
+		return NULL;
 
+	data = arm_lpae_alloc_pgtable(cfg);
 	if (!data)
 		return NULL;
 

drivers/iommu/io-pgtable.c

@@ -33,6 +33,9 @@ io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] =
 	[ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns,
 	[ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns,
 #endif
+#ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S
+	[ARM_V7S] = &io_pgtable_arm_v7s_init_fns,
+#endif
 };
 
 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
@@ -72,6 +75,6 @@ void free_io_pgtable_ops(struct io_pgtable_ops *ops)
 		return;
 
 	iop = container_of(ops, struct io_pgtable, ops);
-	iop->cfg.tlb->tlb_flush_all(iop->cookie);
+	io_pgtable_tlb_flush_all(iop);
 	io_pgtable_init_table[iop->fmt]->free(iop);
 }

drivers/iommu/io-pgtable.h

 #ifndef __IO_PGTABLE_H
 #define __IO_PGTABLE_H
+#include <linux/bitops.h>
 
 /*
  * Public API for use by IOMMU drivers
@@ -9,6 +10,7 @@ enum io_pgtable_fmt {
 	ARM_32_LPAE_S2,
 	ARM_64_LPAE_S1,
 	ARM_64_LPAE_S2,
+	ARM_V7S,
 	IO_PGTABLE_NUM_FMTS,
 };
 
@@ -45,8 +47,24 @@ struct iommu_gather_ops {
  *                 page table walker.
  */
 struct io_pgtable_cfg {
-	#define IO_PGTABLE_QUIRK_ARM_NS	(1 << 0)	/* Set NS bit in PTEs */
-	int				quirks;
+	/*
+	 * IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
+	 *	stage 1 PTEs, for hardware which insists on validating them
+	 *	even in	non-secure state where they should normally be ignored.
+	 *
+	 * IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
+	 *	IOMMU_NOEXEC flags and map everything with full access, for
+	 *	hardware which does not implement the permissions of a given
+	 *	format, and/or requires some format-specific default value.
+	 *
+	 * IO_PGTABLE_QUIRK_TLBI_ON_MAP: If the format forbids caching invalid
+	 *	(unmapped) entries but the hardware might do so anyway, perform
+	 *	TLB maintenance when mapping as well as when unmapping.
+	 */
+	#define IO_PGTABLE_QUIRK_ARM_NS		BIT(0)
+	#define IO_PGTABLE_QUIRK_NO_PERMS	BIT(1)
+	#define IO_PGTABLE_QUIRK_TLBI_ON_MAP	BIT(2)
+	unsigned long			quirks;
 	unsigned long			pgsize_bitmap;
 	unsigned int			ias;
 	unsigned int			oas;
@@ -65,6 +83,13 @@ struct io_pgtable_cfg {
 			u64	vttbr;
 			u64	vtcr;
 		} arm_lpae_s2_cfg;
+
+		struct {
+			u32	ttbr[2];
+			u32	tcr;
+			u32	nmrr;
+			u32	prrr;
+		} arm_v7s_cfg;
 	};
 };
 
@@ -121,18 +146,41 @@ void free_io_pgtable_ops(struct io_pgtable_ops *ops);
  * @fmt:    The page table format.
  * @cookie: An opaque token provided by the IOMMU driver and passed back to
  *          any callback routines.
+ * @tlb_sync_pending: Private flag for optimising out redundant syncs.
  * @cfg:    A copy of the page table configuration.
  * @ops:    The page table operations in use for this set of page tables.
  */
 struct io_pgtable {
 	enum io_pgtable_fmt	fmt;
 	void			*cookie;
+	bool			tlb_sync_pending;
 	struct io_pgtable_cfg	cfg;
 	struct io_pgtable_ops	ops;
 };
 
 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
 
+static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
+{
+	iop->cfg.tlb->tlb_flush_all(iop->cookie);
+	iop->tlb_sync_pending = true;
+}
+
+static inline void io_pgtable_tlb_add_flush(struct io_pgtable *iop,
+		unsigned long iova, size_t size, size_t granule, bool leaf)
+{
+	iop->cfg.tlb->tlb_add_flush(iova, size, granule, leaf, iop->cookie);
+	iop->tlb_sync_pending = true;
+}
+
+static inline void io_pgtable_tlb_sync(struct io_pgtable *iop)
+{
+	if (iop->tlb_sync_pending) {
+		iop->cfg.tlb->tlb_sync(iop->cookie);
+		iop->tlb_sync_pending = false;
+	}
+}
+
 /**
  * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
  *                              particular format.
@@ -149,5 +197,6 @@ extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
 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;
 
 #endif /* __IO_PGTABLE_H */