On Mon 04 May 10:58 PDT 2020, Alex Elder wrote:
> Define a region of IMEM memory available for use by IPA in the
> platform configuration data. Initialize it from ipa_mem_init().
> The memory must be mapped for access through an SMMU.
>
Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Regards,
Bjorn
> Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
> ---
> drivers/net/ipa/ipa.h | 5 ++
> drivers/net/ipa/ipa_data-sc7180.c | 2 +
> drivers/net/ipa/ipa_data-sdm845.c | 2 +
> drivers/net/ipa/ipa_data.h | 6 ++-
> drivers/net/ipa/ipa_mem.c | 84 +++++++++++++++++++++++++++++++
> 5 files changed, 98 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ipa/ipa.h b/drivers/net/ipa/ipa.h
> index 23fb29889e5a..32f6dfafdb05 100644
> --- a/drivers/net/ipa/ipa.h
> +++ b/drivers/net/ipa/ipa.h
> @@ -47,6 +47,8 @@ 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
> * @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 +90,9 @@ struct ipa {
> u32 mem_size;
> const struct ipa_mem *mem;
>
> + unsigned long imem_iova;
> + size_t imem_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 f97e7e4e61c1..e9007d151c68 100644
> --- a/drivers/net/ipa/ipa_data-sc7180.c
> +++ b/drivers/net/ipa/ipa_data-sc7180.c
> @@ -299,6 +299,8 @@ static const struct ipa_mem ipa_mem_local_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,
> };
>
> /* Configuration data for the SC7180 SoC. */
> diff --git a/drivers/net/ipa/ipa_data-sdm845.c b/drivers/net/ipa/ipa_data-sdm845.c
> index c55507e94559..c0e207085550 100644
> --- a/drivers/net/ipa/ipa_data-sdm845.c
> +++ b/drivers/net/ipa/ipa_data-sdm845.c
> @@ -321,6 +321,8 @@ static const struct ipa_mem ipa_mem_local_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,
> };
>
> /* Configuration data for the SDM845 SoC. */
> diff --git a/drivers/net/ipa/ipa_data.h b/drivers/net/ipa/ipa_data.h
> index 51d8e5a6f23a..69957af56ccd 100644
> --- a/drivers/net/ipa/ipa_data.h
> +++ b/drivers/net/ipa/ipa_data.h
> @@ -245,13 +245,17 @@ struct ipa_resource_data {
> };
>
> /**
> - * struct ipa_mem - IPA-local memory region description
> + * 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
> */
> struct ipa_mem_data {
> u32 local_count;
> const struct ipa_mem *local;
> + u32 imem_addr;
> + u32 imem_size;
> };
>
> /**
> diff --git a/drivers/net/ipa/ipa_mem.c b/drivers/net/ipa/ipa_mem.c
> index fb4de2a12796..3c0916597fe1 100644
> --- a/drivers/net/ipa/ipa_mem.c
> +++ b/drivers/net/ipa/ipa_mem.c
> @@ -8,6 +8,7 @@
> #include <linux/bitfield.h>
> #include <linux/bug.h>
> #include <linux/dma-mapping.h>
> +#include <linux/iommu.h>
> #include <linux/io.h>
>
> #include "ipa.h"
> @@ -266,6 +267,79 @@ 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;
> +}
> +
> /* Perform memory region-related initialization */
> int ipa_mem_init(struct ipa *ipa, const struct ipa_mem_data *mem_data)
> {
> @@ -305,11 +379,21 @@ int ipa_mem_init(struct ipa *ipa, const struct ipa_mem_data *mem_data)
> /* The ipa->mem[] array is indexed by enum ipa_mem_id values */
> ipa->mem = mem_data->local;
>
> + ret = ipa_imem_init(ipa, mem_data->imem_addr, mem_data->imem_size);
> + if (ret)
> + goto err_unmap;
> +
> return 0;
> +
> +err_unmap:
> + memunmap(ipa->mem_virt);
> +
> + return ret;
> }
>
> /* Inverse of ipa_mem_init() */
> void ipa_mem_exit(struct ipa *ipa)
> {
> + ipa_imem_exit(ipa);
> memunmap(ipa->mem_virt);
> }
> --
> 2.20.1
>
