[PATCH] soc: qcom: smem: introduce qcom_smem_virt_to_phys()

From: Alex Elder
Date: Wed Apr 25 2018 - 11:18:54 EST


Create function qcom_smem_virt_to_phys(), which returns the physical
address corresponding to a given SMEM item's virtual address. This
feature is required for a driver that will soon be out for review.

Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
---
drivers/soc/qcom/smem.c | 27 +++++++++++++++++++++++++++
include/linux/soc/qcom/smem.h | 2 ++
2 files changed, 29 insertions(+)

diff --git a/drivers/soc/qcom/smem.c b/drivers/soc/qcom/smem.c
index 7d9a43da5084..70b2ee80d6bd 100644
--- a/drivers/soc/qcom/smem.c
+++ b/drivers/soc/qcom/smem.c
@@ -655,6 +655,33 @@ int qcom_smem_get_free_space(unsigned host)
}
EXPORT_SYMBOL(qcom_smem_get_free_space);

+/**
+ * qcom_smem_virt_to_phys() - return the physical address associated
+ * with an smem item pointer (previously returned by qcom_smem_get()
+ * @p: the virtual address to convert
+ *
+ * Returns 0 if the pointer provided is not within any smem region.
+ */
+phys_addr_t qcom_smem_virt_to_phys(void *p)
+{
+ unsigned i;
+
+ for (i = 0; i < __smem->num_regions; i++) {
+ struct smem_region *region = &__smem->regions[i];
+
+ if (p < region->virt_base)
+ continue;
+ if (p < region->virt_base + region->size) {
+ u64 offset = p - region->virt_base;
+
+ return (phys_addr_t)region->aux_base + offset;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(qcom_smem_virt_to_phys);
+
static int qcom_smem_get_sbl_version(struct qcom_smem *smem)
{
struct smem_header *header;
diff --git a/include/linux/soc/qcom/smem.h b/include/linux/soc/qcom/smem.h
index c1657ed27b30..86e1b358688a 100644
--- a/include/linux/soc/qcom/smem.h
+++ b/include/linux/soc/qcom/smem.h
@@ -9,4 +9,6 @@ void *qcom_smem_get(unsigned host, unsigned item, size_t *size);

int qcom_smem_get_free_space(unsigned host);

+phys_addr_t qcom_smem_virt_to_phys(void *p);
+
#endif
--
2.14.1