diff options
Diffstat (limited to 'drivers/net/ipa/ipa_mem.c')
-rw-r--r-- | drivers/net/ipa/ipa_mem.c | 210 |
1 files changed, 205 insertions, 5 deletions
diff --git a/drivers/net/ipa/ipa_mem.c b/drivers/net/ipa/ipa_mem.c index 42d2c29d9f0c..3ef814119aab 100644 --- a/drivers/net/ipa/ipa_mem.c +++ b/drivers/net/ipa/ipa_mem.c @@ -8,19 +8,24 @@ #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" #include "ipa_table.h" #include "gsi_trans.h" /* "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 +270,194 @@ 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 +485,30 @@ 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); } |