[PATCH 9/9] dma_buf: heaps: mtk_sec_heap: Add a new CMA heap
Yong Wu
yong.wu at mediatek.com
Sun Sep 10 19:30:38 PDT 2023
Create a new mtk_svp_cma heap from the CMA reserved buffer.
When the first allocating buffer, use cma_alloc to prepare whole the
CMA range, then send its range to TEE to protect and manage.
For the later allocating, we just adds the cma_used_size.
When SVP done, cma_release will release the buffer, then kernel may
reuse it.
Signed-off-by: Yong Wu <yong.wu at mediatek.com>
---
drivers/dma-buf/heaps/Kconfig | 2 +-
drivers/dma-buf/heaps/mtk_secure_heap.c | 121 +++++++++++++++++++++++-
2 files changed, 119 insertions(+), 4 deletions(-)
diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig
index 729c0cf3eb7c..e101f788ecbf 100644
--- a/drivers/dma-buf/heaps/Kconfig
+++ b/drivers/dma-buf/heaps/Kconfig
@@ -15,7 +15,7 @@ config DMABUF_HEAPS_CMA
config DMABUF_HEAPS_MTK_SECURE
bool "DMA-BUF MediaTek Secure Heap"
- depends on DMABUF_HEAPS && TEE
+ depends on DMABUF_HEAPS && TEE && CMA
help
Choose this option to enable dma-buf MediaTek secure heap for Secure
Video Path. This heap is backed by TEE client interfaces. If in
diff --git a/drivers/dma-buf/heaps/mtk_secure_heap.c b/drivers/dma-buf/heaps/mtk_secure_heap.c
index daf6cf2121a1..3f568fe6b569 100644
--- a/drivers/dma-buf/heaps/mtk_secure_heap.c
+++ b/drivers/dma-buf/heaps/mtk_secure_heap.c
@@ -4,11 +4,12 @@
*
* Copyright (C) 2023 MediaTek Inc.
*/
-
+#include <linux/cma.h>
#include <linux/dma-buf.h>
#include <linux/dma-heap.h>
#include <linux/err.h>
#include <linux/module.h>
+#include <linux/of_reserved_mem.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/tee_drv.h>
@@ -25,9 +26,11 @@
* MediaTek secure (chunk) memory type
*
* @KREE_MEM_SEC_CM_TZ: static chunk memory carved out for trustzone.
+ * @KREE_MEM_SEC_CM_CMA: dynamic chunk memory carved out from CMA.
*/
enum kree_mem_type {
KREE_MEM_SEC_CM_TZ = 1,
+ KREE_MEM_SEC_CM_CMA,
};
struct mtk_secure_heap_buffer {
@@ -42,6 +45,13 @@ struct mtk_secure_heap {
const enum kree_mem_type mem_type;
u32 mem_session;
struct tee_context *tee_ctx;
+
+ struct cma *cma;
+ struct page *cma_page;
+ unsigned long cma_paddr;
+ unsigned long cma_size;
+ unsigned long cma_used_size;
+ struct mutex lock; /* lock for cma_used_size */
};
struct mtk_secure_heap_attachment {
@@ -90,6 +100,42 @@ static int mtk_kree_secure_session_init(struct mtk_secure_heap *sec_heap)
return ret;
}
+static int mtk_sec_mem_cma_allocate(struct mtk_secure_heap *sec_heap, size_t size)
+{
+ /*
+ * Allocate CMA only when allocating buffer for the first time, and just
+ * increase cma_used_size at the other times.
+ */
+ mutex_lock(&sec_heap->lock);
+ if (sec_heap->cma_used_size)
+ goto add_size;
+
+ mutex_unlock(&sec_heap->lock);
+ sec_heap->cma_page = cma_alloc(sec_heap->cma, sec_heap->cma_size >> PAGE_SHIFT,
+ get_order(PAGE_SIZE), false);
+ if (!sec_heap->cma_page)
+ return -ENOMEM;
+
+ mutex_lock(&sec_heap->lock);
+add_size:
+ sec_heap->cma_used_size += size;
+ mutex_unlock(&sec_heap->lock);
+ return sec_heap->cma_used_size;
+}
+
+static void mtk_sec_mem_cma_free(struct mtk_secure_heap *sec_heap, size_t size)
+{
+ bool cma_is_empty;
+
+ mutex_lock(&sec_heap->lock);
+ sec_heap->cma_used_size -= size;
+ cma_is_empty = !sec_heap->cma_used_size;
+ mutex_unlock(&sec_heap->lock);
+
+ if (cma_is_empty)
+ cma_release(sec_heap->cma, sec_heap->cma_page, sec_heap->cma_size >> PAGE_SHIFT);
+}
+
static int
mtk_sec_mem_tee_service_call(struct tee_context *tee_ctx, u32 session,
unsigned int command, struct tee_param *params)
@@ -114,23 +160,47 @@ static int mtk_sec_mem_allocate(struct mtk_secure_heap *sec_heap,
{
struct tee_param params[MTK_TEE_PARAM_NUM] = {0};
u32 mem_session = sec_heap->mem_session;
+ bool cma_frst_alloc = false;
int ret;
+ if (sec_heap->cma) {
+ ret = mtk_sec_mem_cma_allocate(sec_heap, sec_buf->size);
+ if (ret < 0)
+ return ret;
+ /*
+ * When CMA allocates for the first time, pass the CMA range to TEE
+ * to protect it. It's the first allocating if the cma_used_size is equal
+ * to this required buffer size.
+ */
+ cma_frst_alloc = (ret == sec_buf->size);
+ }
+
params[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
params[0].u.value.a = SZ_4K; /* alignment */
params[0].u.value.b = sec_heap->mem_type; /* memory type */
params[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
params[1].u.value.a = sec_buf->size;
params[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
+ if (sec_heap->cma && cma_frst_alloc) {
+ params[2].u.value.a = sec_heap->cma_paddr;
+ params[2].u.value.b = sec_heap->cma_size;
+ }
/* Always request zeroed buffer */
ret = mtk_sec_mem_tee_service_call(sec_heap->tee_ctx, mem_session,
TZCMD_MEM_SECURECM_ZALLOC, params);
- if (ret)
- return -ENOMEM;
+ if (ret) {
+ ret = -ENOMEM;
+ goto free_cma;
+ }
sec_buf->sec_handle = params[2].u.value.a;
return 0;
+
+free_cma:
+ if (sec_heap->cma)
+ mtk_sec_mem_cma_free(sec_heap, sec_buf->size);
+ return ret;
}
static void mtk_sec_mem_release(struct mtk_secure_heap *sec_heap,
@@ -145,6 +215,9 @@ static void mtk_sec_mem_release(struct mtk_secure_heap *sec_heap,
mtk_sec_mem_tee_service_call(sec_heap->tee_ctx, mem_session,
TZCMD_MEM_SECURECM_UNREF, params);
+
+ if (sec_heap->cma)
+ mtk_sec_mem_cma_free(sec_heap, sec_buf->size);
}
static int mtk_sec_heap_attach(struct dma_buf *dmabuf, struct dma_buf_attachment *attachment)
@@ -317,8 +390,41 @@ static struct mtk_secure_heap mtk_sec_heap[] = {
.name = "mtk_svp",
.mem_type = KREE_MEM_SEC_CM_TZ,
},
+ {
+ .name = "mtk_svp_cma",
+ .mem_type = KREE_MEM_SEC_CM_CMA,
+ },
};
+static int __init mtk_secure_cma_init(struct reserved_mem *rmem)
+{
+ struct mtk_secure_heap *sec_heap = NULL;
+ int ret, i;
+
+ for (i = 0; i < ARRAY_SIZE(mtk_sec_heap); i++) {
+ if (mtk_sec_heap[i].mem_type != KREE_MEM_SEC_CM_CMA)
+ continue;
+ sec_heap = &mtk_sec_heap[i];
+ break;
+ }
+ if (!sec_heap)
+ return -ENOENT;
+
+ ret = cma_init_reserved_mem(rmem->base, rmem->size, 0, sec_heap->name,
+ &sec_heap->cma);
+ if (ret) {
+ pr_err("%s: %s set up CMA fail\n", __func__, rmem->name);
+ return ret;
+ }
+ sec_heap->cma_paddr = rmem->base;
+ sec_heap->cma_size = rmem->size;
+
+ return 0;
+}
+
+RESERVEDMEM_OF_DECLARE(mtk_secure_cma, "mediatek,secure_cma_chunkmem",
+ mtk_secure_cma_init);
+
static int mtk_sec_heap_init(void)
{
struct mtk_secure_heap *sec_heap = mtk_sec_heap;
@@ -331,6 +437,15 @@ static int mtk_sec_heap_init(void)
exp_info.ops = &mtk_sec_heap_ops;
exp_info.priv = (void *)sec_heap;
+ if (sec_heap->mem_type == KREE_MEM_SEC_CM_CMA) {
+ if (!sec_heap->cma) {
+ pr_err("CMA is not ready for %s.\n", sec_heap->name);
+ continue;
+ } else {
+ mutex_init(&sec_heap->lock);
+ }
+ }
+
heap = dma_heap_add(&exp_info);
if (IS_ERR(heap))
return PTR_ERR(heap);
--
2.25.1
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