[Linaro-mm-sig] Re: [PATCH 4/9] dma-buf: heaps: Initialise MediaTek secure heap

On 9/11/2023 8:00 AM, Yong Wu wrote:

Initialise a mtk_svp heap. Currently just add a null heap, Prepare for the later patches.

Signed-off-by: Yong Wu yong.wu@mediatek.com

drivers/dma-buf/heaps/Kconfig | 8 ++ drivers/dma-buf/heaps/Makefile | 1 + drivers/dma-buf/heaps/mtk_secure_heap.c | 99 +++++++++++++++++++++++++ 3 files changed, 108 insertions(+) create mode 100644 drivers/dma-buf/heaps/mtk_secure_heap.c

diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig index a5eef06c4226..729c0cf3eb7c 100644 --- a/drivers/dma-buf/heaps/Kconfig +++ b/drivers/dma-buf/heaps/Kconfig @@ -12,3 +12,11 @@ config DMABUF_HEAPS_CMA Choose this option to enable dma-buf CMA heap. This heap is backed by the Contiguous Memory Allocator (CMA). If your system has these regions, you should say Y here.

+config DMABUF_HEAPS_MTK_SECURE

• bool "DMA-BUF MediaTek Secure Heap"
• depends on DMABUF_HEAPS && TEE
• 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
  

•  doubt, say N.
  

diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma-buf/heaps/Makefile index 974467791032..df559dbe33fe 100644 --- a/drivers/dma-buf/heaps/Makefile +++ b/drivers/dma-buf/heaps/Makefile @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_DMABUF_HEAPS_SYSTEM) += system_heap.o obj-$(CONFIG_DMABUF_HEAPS_CMA) += cma_heap.o +obj-$(CONFIG_DMABUF_HEAPS_MTK_SECURE) += mtk_secure_heap.o diff --git a/drivers/dma-buf/heaps/mtk_secure_heap.c b/drivers/dma-buf/heaps/mtk_secure_heap.c new file mode 100644 index 000000000000..bbf1c8dce23e --- /dev/null +++ b/drivers/dma-buf/heaps/mtk_secure_heap.c @@ -0,0 +1,99 @@ +// SPDX-License-Identifier: GPL-2.0 +/*

• • DMABUF mtk_secure_heap exporter
• • Copyright (C) 2023 MediaTek Inc.
• */

+#include <linux/dma-buf.h> +#include <linux/dma-heap.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/slab.h>

+/*

• • MediaTek secure (chunk) memory type
• • @KREE_MEM_SEC_CM_TZ: static chunk memory carved out for trustzone.
• */

+enum kree_mem_type {

• KREE_MEM_SEC_CM_TZ = 1,

+};

+struct mtk_secure_heap_buffer {

• struct dma_heap *heap;
• size_t size;

+};

+struct mtk_secure_heap {

• const char *name;
• const enum kree_mem_type mem_type;

+};

+static struct dma_buf * +mtk_sec_heap_allocate(struct dma_heap *heap, size_t size,

•       unsigned long fd_flags, unsigned long heap_flags)
  

+{

• struct mtk_secure_heap_buffer *sec_buf;
• DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
• struct dma_buf *dmabuf;
• int ret;
• sec_buf = kzalloc(sizeof(*sec_buf), GFP_KERNEL);

As we know, kzalloc can only allocate 4MB at max. So, secure heap has this limitation. can we have a way to allocate more memory in secure heap ? maybe similar to how system heap does?

Thanks, Vijay

• if (!sec_buf)

• return ERR_PTR(-ENOMEM);
  

• sec_buf->size = size;
• sec_buf->heap = heap;
• exp_info.exp_name = dma_heap_get_name(heap);
• exp_info.size = sec_buf->size;
• exp_info.flags = fd_flags;
• exp_info.priv = sec_buf;
• dmabuf = dma_buf_export(&exp_info);
• if (IS_ERR(dmabuf)) {

• ret = PTR_ERR(dmabuf);
  

• goto err_free_buf;
  

• }
• return dmabuf;

+err_free_buf:

• kfree(sec_buf);
• return ERR_PTR(ret);

+}

+static const struct dma_heap_ops mtk_sec_heap_ops = {

• .allocate = mtk_sec_heap_allocate,

+};

+static struct mtk_secure_heap mtk_sec_heap[] = {

• {

• .name		= "mtk_svp",
  

• .mem_type	= KREE_MEM_SEC_CM_TZ,
  

• },

+};

+static int mtk_sec_heap_init(void) +{

• struct mtk_secure_heap *sec_heap = mtk_sec_heap;
• struct dma_heap_export_info exp_info;
• struct dma_heap *heap;
• unsigned int i;
• for (i = 0; i < ARRAY_SIZE(mtk_sec_heap); i++, sec_heap++) {

• exp_info.name = sec_heap->name;
  

• exp_info.ops = &mtk_sec_heap_ops;
  

• exp_info.priv = (void *)sec_heap;
  

• heap = dma_heap_add(&exp_info);
  

• if (IS_ERR(heap))
  

• 	return PTR_ERR(heap);
  

• }
• return 0;

+}

+module_init(mtk_sec_heap_init); +MODULE_DESCRIPTION("MediaTek Secure Heap Driver"); +MODULE_LICENSE("GPL");