80dc47c198352377220653c7c659d43e32d7553a920f6d5acf961d38.patch

From 21d0abb187f1aff8ca9d3b1e7bbae95cf50eb732 Mon Sep 17 00:00:00 2001
From: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Date: Wed, 30 Aug 2023 01:49:43 +0530
Subject: [PATCH] FROMLIST: tee: amdtee: add support for CMA buffer allocations

amdtee driver shall use CMA region for contiguous
buffer allocation, if CMA is available.

since CMA and DMA contiguous APIs are not exported,
this support is enabled only when amdtee is built
as a builtin driver.

Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: SivaSangeetha SK <SivaSangeetha.SK@amd.com>
Reviewed-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
(am from https://lore.kernel.org/r/8c7f0641582d53c20c6657f0ebb4d3a1279e6f9b.1693340098.git.Devaraj.Rangasamy@amd.com)

BUG=b:285231416
UPSTREAM-TASK=b:308177821
TEST=CQ

Change-Id: I01ac17b777569ee668b53aac24eddd9ece37df11
Signed-off-by: Tim Van Patten <timvp@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/4982593
Reviewed-by: Mark Hasemeyer <markhas@google.com>
---
 drivers/tee/amdtee/shm_pool.c | 51 +++++++++++++++++++++++++++++++++--
 1 file changed, 49 insertions(+), 2 deletions(-)

diff --git a/drivers/tee/amdtee/shm_pool.c b/drivers/tee/amdtee/shm_pool.c
index 7251dedd2890cc9eb88cdb3a8936b46cb262576d..613ce162b807f9546bd1f1fb4affb0fa2432f10f 100644
--- a/drivers/tee/amdtee/shm_pool.c
+++ b/drivers/tee/amdtee/shm_pool.c
@@ -5,10 +5,50 @@
 
 #include <linux/slab.h>
 #include <linux/mm.h>
+#include <linux/dma-map-ops.h>
 #include <linux/tee_core.h>
 #include <linux/psp.h>
 #include "amdtee_private.h"
 
+#if IS_BUILTIN(CONFIG_AMDTEE) && IS_ENABLED(CONFIG_DMA_CMA)
+static void *alloc_from_cma(size_t size)
+{
+
+	int nr_pages = size >> PAGE_SHIFT;
+	struct page *page;
+
+	page = dma_alloc_from_contiguous(NULL, nr_pages, 0, false);
+	if (page)
+		return page_to_virt(page);
+
+	return NULL;
+}
+
+static bool free_from_cma(struct tee_shm *shm)
+{
+
+	int nr_pages;
+	struct page *page;
+
+	if (!dev_get_cma_area(NULL))
+		return false;
+
+	nr_pages = shm->size >> PAGE_SHIFT;
+	page = virt_to_page(shm->kaddr);
+	return dma_release_from_contiguous(NULL, page, nr_pages);
+}
+#else
+static void *alloc_from_cma(size_t size)
+{
+	return NULL;
+}
+
+static bool free_from_cma(struct tee_shm *shm)
+{
+	return false;
+}
+#endif
+
 static int pool_op_alloc(struct tee_shm_pool *pool, struct tee_shm *shm,
 			 size_t size, size_t align)
 {
@@ -17,7 +57,11 @@ static int pool_op_alloc(struct tee_shm_pool *pool, struct tee_shm *shm,
 
 	size = PAGE_ALIGN(size);
 
-	va = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
+	va = alloc_from_cma(size);
+
+	if (!va)
+		va = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
+
 	if (!va)
 		return -ENOMEM;
 
@@ -40,7 +84,10 @@ static void pool_op_free(struct tee_shm_pool *pool, struct tee_shm *shm)
 {
 	/* Unmap the shared memory from TEE */
 	amdtee_unmap_shmem(shm);
-	free_pages_exact(shm->kaddr, shm->size);
+
+	if (!free_from_cma(shm))
+		free_pages_exact(shm->kaddr, shm->size);
+
 	shm->kaddr = NULL;
 }
 
-- 
2.45.1.288.g0e0cd299f1-goog