Merge tag 'iommu-updates-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull IOMMU updates from Joerg Roedel:

 - updates for the Exynos IOMMU driver to make use of default domains
   and to add support for the SYSMMU v5

 - new Mediatek IOMMU driver

 - support for the ARMv7 short descriptor format in the io-pgtable code

 - default domain support for the ARM SMMU

 - couple of other small fixes all over the place

* tag 'iommu-updates-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (41 commits)
  iommu/ipmmu-vmsa: Add r8a7795 DT binding
  iommu/mediatek: Check for NULL instead of IS_ERR()
  iommu/io-pgtable-armv7s: Fix kmem_cache_alloc() flags
  iommu/mediatek: Fix handling of of_count_phandle_with_args result
  iommu/dma: Fix NEED_SG_DMA_LENGTH dependency
  iommu/mediatek: Mark PM functions as __maybe_unused
  iommu/mediatek: Select ARM_DMA_USE_IOMMU
  iommu/exynos: Use proper readl/writel register interface
  iommu/exynos: Pointers are nto physical addresses
  dts: mt8173: Add iommu/smi nodes for mt8173
  iommu/mediatek: Add mt8173 IOMMU driver
  memory: mediatek: Add SMI driver
  dt-bindings: mediatek: Add smi dts binding
  dt-bindings: iommu: Add binding for mediatek IOMMU
  iommu/ipmmu-vmsa: Use ARCH_RENESAS
  iommu/exynos: Support multiple attach_device calls
  iommu/exynos: Add Maintainers entry for Exynos SYSMMU driver
  iommu/exynos: Add support for v5 SYSMMU
  iommu/exynos: Update device tree documentation
  iommu/exynos: Add support for SYSMMU controller with bogus version reg
  ...

1 files changed, 50 insertions, 29 deletions

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 59ee4b8a3236..2409e3bd3df2 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -29,6 +29,7 @@
 #define pr_fmt(fmt) "arm-smmu: " fmt
 
 #include <linux/delay.h>
+#include <linux/dma-iommu.h>
 #include <linux/dma-mapping.h>
 #include <linux/err.h>
 #include <linux/interrupt.h>
@@ -167,6 +168,9 @@
 #define S2CR_TYPE_BYPASS		(1 << S2CR_TYPE_SHIFT)
 #define S2CR_TYPE_FAULT			(2 << S2CR_TYPE_SHIFT)
 
+#define S2CR_PRIVCFG_SHIFT		24
+#define S2CR_PRIVCFG_UNPRIV		(2 << S2CR_PRIVCFG_SHIFT)
+
 /* Context bank attribute registers */
 #define ARM_SMMU_GR1_CBAR(n)		(0x0 + ((n) << 2))
 #define CBAR_VMID_SHIFT			0
@@ -257,9 +261,13 @@
 #define FSYNR0_WNR			(1 << 4)
 
 static int force_stage;
-module_param_named(force_stage, force_stage, int, S_IRUGO);
+module_param(force_stage, int, S_IRUGO);
 MODULE_PARM_DESC(force_stage,
 	"Force SMMU mappings to be installed at a particular stage of translation. A value of '1' or '2' forces the corresponding stage. All other values are ignored (i.e. no stage is forced). Note that selecting a specific stage will disable support for nested translation.");
+static bool disable_bypass;
+module_param(disable_bypass, bool, S_IRUGO);
+MODULE_PARM_DESC(disable_bypass,
+	"Disable bypass streams such that incoming transactions from devices that are not attached to an iommu domain will report an abort back to the device and will not be allowed to pass through the SMMU.");
 
 enum arm_smmu_arch_version {
 	ARM_SMMU_V1 = 1,
@@ -963,7 +971,7 @@ static struct iommu_domain *arm_smmu_domain_alloc(unsigned type)
 {
 	struct arm_smmu_domain *smmu_domain;
 
-	if (type != IOMMU_DOMAIN_UNMANAGED)
+	if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA)
 		return NULL;
 	/*
 	 * Allocate the domain and initialise some of its data structures.
@@ -974,6 +982,12 @@ static struct iommu_domain *arm_smmu_domain_alloc(unsigned type)
 	if (!smmu_domain)
 		return NULL;
 
+	if (type == IOMMU_DOMAIN_DMA &&
+	    iommu_get_dma_cookie(&smmu_domain->domain)) {
+		kfree(smmu_domain);
+		return NULL;
+	}
+
 	mutex_init(&smmu_domain->init_mutex);
 	spin_lock_init(&smmu_domain->pgtbl_lock);
 
@@ -988,6 +1002,7 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
 	 * Free the domain resources. We assume that all devices have
 	 * already been detached.
 	 */
+	iommu_put_dma_cookie(domain);
 	arm_smmu_destroy_domain_context(domain);
 	kfree(smmu_domain);
 }
@@ -1079,11 +1094,18 @@ static int arm_smmu_domain_add_master(struct arm_smmu_domain *smmu_domain,
 	if (ret)
 		return ret == -EEXIST ? 0 : ret;
 
+	/*
+	 * FIXME: This won't be needed once we have IOMMU-backed DMA ops
+	 * for all devices behind the SMMU.
+	 */
+	if (smmu_domain->domain.type == IOMMU_DOMAIN_DMA)
+		return 0;
+
 	for (i = 0; i < cfg->num_streamids; ++i) {
 		u32 idx, s2cr;
 
 		idx = cfg->smrs ? cfg->smrs[i].idx : cfg->streamids[i];
-		s2cr = S2CR_TYPE_TRANS |
+		s2cr = S2CR_TYPE_TRANS | S2CR_PRIVCFG_UNPRIV |
 		       (smmu_domain->cfg.cbndx << S2CR_CBNDX_SHIFT);
 		writel_relaxed(s2cr, gr0_base + ARM_SMMU_GR0_S2CR(idx));
 	}
@@ -1108,14 +1130,24 @@ static void arm_smmu_domain_remove_master(struct arm_smmu_domain *smmu_domain,
 	 */
 	for (i = 0; i < cfg->num_streamids; ++i) {
 		u32 idx = cfg->smrs ? cfg->smrs[i].idx : cfg->streamids[i];
+		u32 reg = disable_bypass ? S2CR_TYPE_FAULT : S2CR_TYPE_BYPASS;
 
-		writel_relaxed(S2CR_TYPE_BYPASS,
-			       gr0_base + ARM_SMMU_GR0_S2CR(idx));
+		writel_relaxed(reg, gr0_base + ARM_SMMU_GR0_S2CR(idx));
 	}
 
 	arm_smmu_master_free_smrs(smmu, cfg);
 }
 
+static void arm_smmu_detach_dev(struct device *dev,
+				struct arm_smmu_master_cfg *cfg)
+{
+	struct iommu_domain *domain = dev->archdata.iommu;
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+
+	dev->archdata.iommu = NULL;
+	arm_smmu_domain_remove_master(smmu_domain, cfg);
+}
+
 static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 {
 	int ret;
@@ -1129,11 +1161,6 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 		return -ENXIO;
 	}
 
-	if (dev->archdata.iommu) {
-		dev_err(dev, "already attached to IOMMU domain\n");
-		return -EEXIST;
-	}
-
 	/* Ensure that the domain is finalised */
 	ret = arm_smmu_init_domain_context(domain, smmu);
 	if (IS_ERR_VALUE(ret))
@@ -1155,25 +1182,16 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 	if (!cfg)
 		return -ENODEV;
 
+	/* Detach the dev from its current domain */
+	if (dev->archdata.iommu)
+		arm_smmu_detach_dev(dev, cfg);
+
 	ret = arm_smmu_domain_add_master(smmu_domain, cfg);
 	if (!ret)
 		dev->archdata.iommu = domain;
 	return ret;
 }
 
-static void arm_smmu_detach_dev(struct iommu_domain *domain, struct device *dev)
-{
-	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
-	struct arm_smmu_master_cfg *cfg;
-
-	cfg = find_smmu_master_cfg(dev);
-	if (!cfg)
-		return;
-
-	dev->archdata.iommu = NULL;
-	arm_smmu_domain_remove_master(smmu_domain, cfg);
-}
-
 static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova,
 			phys_addr_t paddr, size_t size, int prot)
 {
@@ -1449,7 +1467,6 @@ static struct iommu_ops arm_smmu_ops = {
 	.domain_alloc		= arm_smmu_domain_alloc,
 	.domain_free		= arm_smmu_domain_free,
 	.attach_dev		= arm_smmu_attach_dev,
-	.detach_dev		= arm_smmu_detach_dev,
 	.map			= arm_smmu_map,
 	.unmap			= arm_smmu_unmap,
 	.map_sg			= default_iommu_map_sg,
@@ -1473,11 +1490,11 @@ static void arm_smmu_device_reset(struct arm_smmu_device *smmu)
 	reg = readl_relaxed(ARM_SMMU_GR0_NS(smmu) + ARM_SMMU_GR0_sGFSR);
 	writel(reg, ARM_SMMU_GR0_NS(smmu) + ARM_SMMU_GR0_sGFSR);
 
-	/* Mark all SMRn as invalid and all S2CRn as bypass */
+	/* Mark all SMRn as invalid and all S2CRn as bypass unless overridden */
+	reg = disable_bypass ? S2CR_TYPE_FAULT : S2CR_TYPE_BYPASS;
 	for (i = 0; i < smmu->num_mapping_groups; ++i) {
 		writel_relaxed(0, gr0_base + ARM_SMMU_GR0_SMR(i));
-		writel_relaxed(S2CR_TYPE_BYPASS,
-			gr0_base + ARM_SMMU_GR0_S2CR(i));
+		writel_relaxed(reg, gr0_base + ARM_SMMU_GR0_S2CR(i));
 	}
 
 	/* Make sure all context banks are disabled and clear CB_FSR  */
@@ -1499,8 +1516,12 @@ static void arm_smmu_device_reset(struct arm_smmu_device *smmu)
 	/* Disable TLB broadcasting. */
 	reg |= (sCR0_VMIDPNE | sCR0_PTM);
 
-	/* Enable client access, but bypass when no mapping is found */
-	reg &= ~(sCR0_CLIENTPD | sCR0_USFCFG);
+	/* Enable client access, handling unmatched streams as appropriate */
+	reg &= ~sCR0_CLIENTPD;
+	if (disable_bypass)
+		reg |= sCR0_USFCFG;
+	else
+		reg &= ~sCR0_USFCFG;
 
 	/* Disable forced broadcasting */
 	reg &= ~sCR0_FB;