Merge branch 'net-ipa-I-O-map-SMEM-and-IMEM'

Alex Elder says:

====================
net: ipa: I/O map SMEM and IMEM

This series adds the definition of two memory regions that must be
mapped for IPA to access through an SMMU.  It requires the SMMU to
be defined in the IPA node in the SoC's Device Tree file.

There is no change since version 1 to the content of the code in
these patches, *however* this time the first patch is an update to
the binding definition rather than an update to a DTS file.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 263 insertions, 22 deletions

diff --git a/Documentation/devicetree/bindings/net/qcom,ipa.yaml b/Documentation/devicetree/bindings/net/qcom,ipa.yaml
index 140f15245654..7b749fc04c32 100644
--- a/Documentation/devicetree/bindings/net/qcom,ipa.yaml
+++ b/Documentation/devicetree/bindings/net/qcom,ipa.yaml
@@ -20,7 +20,10 @@ description:
   The GSI is an integral part of the IPA, but it is logically isolated
   and has a distinct interrupt and a separately-defined address space.
 
-  See also soc/qcom/qcom,smp2p.txt and interconnect/interconnect.txt.
+  See also soc/qcom/qcom,smp2p.txt and interconnect/interconnect.txt.  See
+  iommu/iommu.txt and iommu/arm,smmu.yaml for more information about SMMU
+  bindings.
+
 
   - |
     --------             ---------
@@ -54,6 +57,9 @@ properties:
       - const: ipa-shared
       - const: gsi
 
+  iommus:
+    maxItems: 1
+
   clocks:
     maxItems: 1
 
@@ -126,6 +132,7 @@ properties:
 
 required:
   - compatible
+  - iommus
   - reg
   - clocks
   - interrupts
@@ -164,6 +171,7 @@ examples:
                 modem-init;
                 modem-remoteproc = <&mss_pil>;
 
+                iommus = <&apps_smmu 0x720 0x3>;
                 reg = <0 0x1e40000 0 0x7000>,
                         <0 0x1e47000 0 0x2000>,
                         <0 0x1e04000 0 0x2c000>;
diff --git a/drivers/net/ipa/ipa.h b/drivers/net/ipa/ipa.h
index 23fb29889e5a..b10a85392952 100644
--- a/drivers/net/ipa/ipa.h
+++ b/drivers/net/ipa/ipa.h
@@ -47,6 +47,10 @@ struct ipa_interrupt;
  * @mem_offset:		Offset from @mem_virt used for access to IPA memory
  * @mem_size:		Total size (bytes) of memory at @mem_virt
  * @mem:		Array of IPA-local memory region descriptors
+ * @imem_iova:		I/O virtual address of IPA region in IMEM
+ * @imem_size;		Size of IMEM region
+ * @smem_iova:		I/O virtual address of IPA region in SMEM
+ * @smem_size;		Size of SMEM region
  * @zero_addr:		DMA address of preallocated zero-filled memory
  * @zero_virt:		Virtual address of preallocated zero-filled memory
  * @zero_size:		Size (bytes) of preallocated zero-filled memory
@@ -88,6 +92,12 @@ struct ipa {
 	u32 mem_size;
 	const struct ipa_mem *mem;
 
+	unsigned long imem_iova;
+	size_t imem_size;
+
+	unsigned long smem_iova;
+	size_t smem_size;
+
 	dma_addr_t zero_addr;
 	void *zero_virt;
 	size_t zero_size;
diff --git a/drivers/net/ipa/ipa_data-sc7180.c b/drivers/net/ipa/ipa_data-sc7180.c
index 042b5fc3c135..43faa35ae726 100644
--- a/drivers/net/ipa/ipa_data-sc7180.c
+++ b/drivers/net/ipa/ipa_data-sc7180.c
@@ -193,7 +193,7 @@ static const struct ipa_resource_data ipa_resource_data = {
 };
 
 /* IPA-resident memory region configuration for the SC7180 SoC. */
-static const struct ipa_mem ipa_mem_data[] = {
+static const struct ipa_mem ipa_mem_local_data[] = {
 	[IPA_MEM_UC_SHARED] = {
 		.offset		= 0x0000,
 		.size		= 0x0080,
@@ -296,12 +296,20 @@ static const struct ipa_mem ipa_mem_data[] = {
 	},
 };
 
+static struct ipa_mem_data ipa_mem_data = {
+	.local_count	= ARRAY_SIZE(ipa_mem_local_data),
+	.local		= ipa_mem_local_data,
+	.imem_addr	= 0x146a8000,
+	.imem_size	= 0x00002000,
+	.smem_id	= 497,
+	.smem_size	= 0x00002000,
+};
+
 /* Configuration data for the SC7180 SoC. */
 const struct ipa_data ipa_data_sc7180 = {
 	.version	= IPA_VERSION_4_2,
 	.endpoint_count	= ARRAY_SIZE(ipa_gsi_endpoint_data),
 	.endpoint_data	= ipa_gsi_endpoint_data,
 	.resource_data	= &ipa_resource_data,
-	.mem_count	= ARRAY_SIZE(ipa_mem_data),
-	.mem_data	= ipa_mem_data,
+	.mem_data	= &ipa_mem_data,
 };
diff --git a/drivers/net/ipa/ipa_data-sdm845.c b/drivers/net/ipa/ipa_data-sdm845.c
index 0d9c36e1e806..f7ba85717edf 100644
--- a/drivers/net/ipa/ipa_data-sdm845.c
+++ b/drivers/net/ipa/ipa_data-sdm845.c
@@ -235,7 +235,7 @@ static const struct ipa_resource_data ipa_resource_data = {
 };
 
 /* IPA-resident memory region configuration for the SDM845 SoC. */
-static const struct ipa_mem ipa_mem_data[] = {
+static const struct ipa_mem ipa_mem_local_data[] = {
 	[IPA_MEM_UC_SHARED] = {
 		.offset		= 0x0000,
 		.size		= 0x0080,
@@ -318,12 +318,20 @@ static const struct ipa_mem ipa_mem_data[] = {
 	},
 };
 
+static struct ipa_mem_data ipa_mem_data = {
+	.local_count	= ARRAY_SIZE(ipa_mem_local_data),
+	.local		= ipa_mem_local_data,
+	.imem_addr	= 0x146bd000,
+	.imem_size	= 0x00002000,
+	.smem_id	= 497,
+	.smem_size	= 0x00002000,
+};
+
 /* Configuration data for the SDM845 SoC. */
 const struct ipa_data ipa_data_sdm845 = {
 	.version	= IPA_VERSION_3_5_1,
 	.endpoint_count	= ARRAY_SIZE(ipa_gsi_endpoint_data),
 	.endpoint_data	= ipa_gsi_endpoint_data,
 	.resource_data	= &ipa_resource_data,
-	.mem_count	= ARRAY_SIZE(ipa_mem_data),
-	.mem_data	= ipa_mem_data,
+	.mem_data	= &ipa_mem_data,
 };
diff --git a/drivers/net/ipa/ipa_data.h b/drivers/net/ipa/ipa_data.h
index 7110de2de817..16dfd74717b1 100644
--- a/drivers/net/ipa/ipa_data.h
+++ b/drivers/net/ipa/ipa_data.h
@@ -245,15 +245,21 @@ struct ipa_resource_data {
 };
 
 /**
- * struct ipa_mem - IPA-local memory region description
- * @offset:		offset in IPA memory space to base of the region
- * @size:		size in bytes base of the region
- * @canary_count:	number of 32-bit "canary" values that precede region
+ * struct ipa_mem - description of IPA memory regions
+ * @local_count:	number of regions defined in the local[] array
+ * @local:		array of IPA-local memory region descriptors
+ * @imem_addr:		physical address of IPA region within IMEM
+ * @imem_size:		size in bytes of IPA IMEM region
+ * @smem_id:		item identifier for IPA region within SMEM memory
+ * @imem_size:		size in bytes of the IPA SMEM region
  */
 struct ipa_mem_data {
-	u32 offset;
-	u16 size;
-	u16 canary_count;
+	u32 local_count;
+	const struct ipa_mem *local;
+	u32 imem_addr;
+	u32 imem_size;
+	u32 smem_id;
+	u32 smem_size;
 };
 
 /**
@@ -270,8 +276,7 @@ struct ipa_data {
 	u32 endpoint_count;	/* # entries in endpoint_data[] */
 	const struct ipa_gsi_endpoint_data *endpoint_data;
 	const struct ipa_resource_data *resource_data;
-	u32 mem_count;		/* # entries in mem_data[] */
-	const struct ipa_mem *mem_data;
+	const struct ipa_mem_data *mem_data;
 };
 
 extern const struct ipa_data ipa_data_sdm845;
diff --git a/drivers/net/ipa/ipa_main.c b/drivers/net/ipa/ipa_main.c
index 28998dcce3d2..9295a9122e8e 100644
--- a/drivers/net/ipa/ipa_main.c
+++ b/drivers/net/ipa/ipa_main.c
@@ -778,7 +778,7 @@ static int ipa_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_kfree_ipa;
 
-	ret = ipa_mem_init(ipa, data->mem_count, data->mem_data);
+	ret = ipa_mem_init(ipa, data->mem_data);
 	if (ret)
 		goto err_reg_exit;
 
diff --git a/drivers/net/ipa/ipa_mem.c b/drivers/net/ipa/ipa_mem.c
index 42d2c29d9f0c..aa8f6b0f3d50 100644
--- a/drivers/net/ipa/ipa_mem.c
+++ b/drivers/net/ipa/ipa_mem.c
@@ -8,10 +8,13 @@
 #include <linux/bitfield.h>
 #include <linux/bug.h>
 #include <linux/dma-mapping.h>
+#include <linux/iommu.h>
 #include <linux/io.h>
+#include <linux/soc/qcom/smem.h>
 
 #include "ipa.h"
 #include "ipa_reg.h"
+#include "ipa_data.h"
 #include "ipa_cmd.h"
 #include "ipa_mem.h"
 #include "ipa_data.h"
@@ -21,6 +24,9 @@
 /* "Canary" value placed between memory regions to detect overflow */
 #define IPA_MEM_CANARY_VAL		cpu_to_le32(0xdeadbeef)
 
+/* SMEM host id representing the modem. */
+#define QCOM_SMEM_HOST_MODEM	1
+
 /* Add an immediate command to a transaction that zeroes a memory region */
 static void
 ipa_mem_zero_region_add(struct gsi_trans *trans, const struct ipa_mem *mem)
@@ -265,16 +271,194 @@ int ipa_mem_zero_modem(struct ipa *ipa)
 	return 0;
 }
 
+/**
+ * ipa_imem_init() - Initialize IMEM memory used by the IPA
+ * @ipa:	IPA pointer
+ * @addr:	Physical address of the IPA region in IMEM
+ * @size:	Size (bytes) of the IPA region in IMEM
+ *
+ * IMEM is a block of shared memory separate from system DRAM, and
+ * a portion of this memory is available for the IPA to use.  The
+ * modem accesses this memory directly, but the IPA accesses it
+ * via the IOMMU, using the AP's credentials.
+ *
+ * If this region exists (size > 0) we map it for read/write access
+ * through the IOMMU using the IPA device.
+ *
+ * Note: @addr and @size are not guaranteed to be page-aligned.
+ */
+static int ipa_imem_init(struct ipa *ipa, unsigned long addr, size_t size)
+{
+	struct device *dev = &ipa->pdev->dev;
+	struct iommu_domain *domain;
+	unsigned long iova;
+	phys_addr_t phys;
+	int ret;
+
+	if (!size)
+		return 0;	/* IMEM memory not used */
+
+	domain = iommu_get_domain_for_dev(dev);
+	if (!domain) {
+		dev_err(dev, "no IOMMU domain found for IMEM\n");
+		return -EINVAL;
+	}
+
+	/* Align the address down and the size up to page boundaries */
+	phys = addr & PAGE_MASK;
+	size = PAGE_ALIGN(size + addr - phys);
+	iova = phys;	/* We just want a direct mapping */
+
+	ret = iommu_map(domain, iova, phys, size, IOMMU_READ | IOMMU_WRITE);
+	if (ret)
+		return ret;
+
+	ipa->imem_iova = iova;
+	ipa->imem_size = size;
+
+	return 0;
+}
+
+static void ipa_imem_exit(struct ipa *ipa)
+{
+	struct iommu_domain *domain;
+	struct device *dev;
+
+	if (!ipa->imem_size)
+		return;
+
+	dev = &ipa->pdev->dev;
+	domain = iommu_get_domain_for_dev(dev);
+	if (domain) {
+		size_t size;
+
+		size = iommu_unmap(domain, ipa->imem_iova, ipa->imem_size);
+		if (size != ipa->imem_size)
+			dev_warn(dev, "unmapped %zu IMEM bytes, expected %lu\n",
+				 size, ipa->imem_size);
+	} else {
+		dev_err(dev, "couldn't get IPA IOMMU domain for IMEM\n");
+	}
+
+	ipa->imem_size = 0;
+	ipa->imem_iova = 0;
+}
+
+/**
+ * ipa_smem_init() - Initialize SMEM memory used by the IPA
+ * @ipa:	IPA pointer
+ * @item:	Item ID of SMEM memory
+ * @size:	Size (bytes) of SMEM memory region
+ *
+ * SMEM is a managed block of shared DRAM, from which numbered "items"
+ * can be allocated.  One item is designated for use by the IPA.
+ *
+ * The modem accesses SMEM memory directly, but the IPA accesses it
+ * via the IOMMU, using the AP's credentials.
+ *
+ * If size provided is non-zero, we allocate it and map it for
+ * access through the IOMMU.
+ *
+ * Note: @size and the item address are is not guaranteed to be page-aligned.
+ */
+static int ipa_smem_init(struct ipa *ipa, u32 item, size_t size)
+{
+	struct device *dev = &ipa->pdev->dev;
+	struct iommu_domain *domain;
+	unsigned long iova;
+	phys_addr_t phys;
+	phys_addr_t addr;
+	size_t actual;
+	void *virt;
+	int ret;
+
+	if (!size)
+		return 0;	/* SMEM memory not used */
+
+	/* SMEM is memory shared between the AP and another system entity
+	 * (in this case, the modem).  An allocation from SMEM is persistent
+	 * until the AP reboots; there is no way to free an allocated SMEM
+	 * region.  Allocation only reserves the space; to use it you need
+	 * to "get" a pointer it (this implies no reference counting).
+	 * The item might have already been allocated, in which case we
+	 * use it unless the size isn't what we expect.
+	 */
+	ret = qcom_smem_alloc(QCOM_SMEM_HOST_MODEM, item, size);
+	if (ret && ret != -EEXIST) {
+		dev_err(dev, "error %d allocating size %zu SMEM item %u\n",
+			ret, size, item);
+		return ret;
+	}
+
+	/* Now get the address of the SMEM memory region */
+	virt = qcom_smem_get(QCOM_SMEM_HOST_MODEM, item, &actual);
+	if (IS_ERR(virt)) {
+		ret = PTR_ERR(virt);
+		dev_err(dev, "error %d getting SMEM item %u\n", ret, item);
+		return ret;
+	}
+
+	/* In case the region was already allocated, verify the size */
+	if (ret && actual != size) {
+		dev_err(dev, "SMEM item %u has size %zu, expected %zu\n",
+			item, actual, size);
+		return -EINVAL;
+	}
+
+	domain = iommu_get_domain_for_dev(dev);
+	if (!domain) {
+		dev_err(dev, "no IOMMU domain found for SMEM\n");
+		return -EINVAL;
+	}
+
+	/* Align the address down and the size up to a page boundary */
+	addr = qcom_smem_virt_to_phys(virt) & PAGE_MASK;
+	phys = addr & PAGE_MASK;
+	size = PAGE_ALIGN(size + addr - phys);
+	iova = phys;	/* We just want a direct mapping */
+
+	ret = iommu_map(domain, iova, phys, size, IOMMU_READ | IOMMU_WRITE);
+	if (ret)
+		return ret;
+
+	ipa->smem_iova = iova;
+	ipa->smem_size = size;
+
+	return 0;
+}
+
+static void ipa_smem_exit(struct ipa *ipa)
+{
+	struct device *dev = &ipa->pdev->dev;
+	struct iommu_domain *domain;
+
+	domain = iommu_get_domain_for_dev(dev);
+	if (domain) {
+		size_t size;
+
+		size = iommu_unmap(domain, ipa->smem_iova, ipa->smem_size);
+		if (size != ipa->smem_size)
+			dev_warn(dev, "unmapped %zu SMEM bytes, expected %lu\n",
+				 size, ipa->smem_size);
+
+	} else {
+		dev_err(dev, "couldn't get IPA IOMMU domain for SMEM\n");
+	}
+
+	ipa->smem_size = 0;
+	ipa->smem_iova = 0;
+}
+
 /* Perform memory region-related initialization */
-int ipa_mem_init(struct ipa *ipa, u32 count, const struct ipa_mem *mem)
+int ipa_mem_init(struct ipa *ipa, const struct ipa_mem_data *mem_data)
 {
 	struct device *dev = &ipa->pdev->dev;
 	struct resource *res;
 	int ret;
 
-	if (count > IPA_MEM_COUNT) {
+	if (mem_data->local_count > IPA_MEM_COUNT) {
 		dev_err(dev, "to many memory regions (%u > %u)\n",
-			count, IPA_MEM_COUNT);
+			mem_data->local_count, IPA_MEM_COUNT);
 		return -EINVAL;
 	}
 
@@ -302,13 +486,30 @@ int ipa_mem_init(struct ipa *ipa, u32 count, const struct ipa_mem *mem)
 	ipa->mem_size = resource_size(res);
 
 	/* The ipa->mem[] array is indexed by enum ipa_mem_id values */
-	ipa->mem = mem;
+	ipa->mem = mem_data->local;
+
+	ret = ipa_imem_init(ipa, mem_data->imem_addr, mem_data->imem_size);
+	if (ret)
+		goto err_unmap;
+
+	ret = ipa_smem_init(ipa, mem_data->smem_id, mem_data->smem_size);
+	if (ret)
+		goto err_imem_exit;
 
 	return 0;
+
+err_imem_exit:
+	ipa_imem_exit(ipa);
+err_unmap:
+	memunmap(ipa->mem_virt);
+
+	return ret;
 }
 
 /* Inverse of ipa_mem_init() */
 void ipa_mem_exit(struct ipa *ipa)
 {
+	ipa_smem_exit(ipa);
+	ipa_imem_exit(ipa);
 	memunmap(ipa->mem_virt);
 }
diff --git a/drivers/net/ipa/ipa_mem.h b/drivers/net/ipa/ipa_mem.h
index 065cb499ebe5..f99180f84f0d 100644
--- a/drivers/net/ipa/ipa_mem.h
+++ b/drivers/net/ipa/ipa_mem.h
@@ -7,6 +7,7 @@
 #define _IPA_MEM_H_
 
 struct ipa;
+struct ipa_mem_data;
 
 /**
  * DOC: IPA Local Memory
@@ -84,7 +85,7 @@ void ipa_mem_teardown(struct ipa *ipa);
 
 int ipa_mem_zero_modem(struct ipa *ipa);
 
-int ipa_mem_init(struct ipa *ipa, u32 count, const struct ipa_mem *mem);
+int ipa_mem_init(struct ipa *ipa, const struct ipa_mem_data *mem_data);
 void ipa_mem_exit(struct ipa *ipa);
 
 #endif /* _IPA_MEM_H_ */