[PATCH 5/9] dma-buf: heaps: mtk_sec_heap: Initialise tee session

[Yong Wu]

The TEE probe later than dma-buf heap, and PROBE_DEDER doesn't work
here since this is not a platform driver, therefore initialise the TEE
context/session while we allocate the first secure buffer.

Signed-off-by: Yong Wu <yong...@mediatek.com>
---
 drivers/dma-buf/heaps/mtk_secure_heap.c | 61 +++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/drivers/dma-buf/heaps/mtk_secure_heap.c 
b/drivers/dma-buf/heaps/mtk_secure_heap.c
index bbf1c8dce23e..e3da33a3d083 100644
--- a/drivers/dma-buf/heaps/mtk_secure_heap.c
+++ b/drivers/dma-buf/heaps/mtk_secure_heap.c
@@ -10,6 +10,12 @@
 #include <linux/err.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/tee_drv.h>
+#include <linux/uuid.h>
+
+#define TZ_TA_MEM_UUID         "4477588a-8476-11e2-ad15-e41f1390d676"
+
+#define MTK_TEE_PARAM_NUM              4
 
 /*
  * MediaTek secure (chunk) memory type
@@ -28,17 +34,72 @@ struct mtk_secure_heap_buffer {
 struct mtk_secure_heap {
        const char              *name;
        const enum kree_mem_type mem_type;
+       u32                      mem_session;
+       struct tee_context      *tee_ctx;
 };
 
+static int mtk_optee_ctx_match(struct tee_ioctl_version_data *ver, const void 
*data)
+{
+       return ver->impl_id == TEE_IMPL_ID_OPTEE;
+}
+
+static int mtk_kree_secure_session_init(struct mtk_secure_heap *sec_heap)
+{
+       struct tee_param t_param[MTK_TEE_PARAM_NUM] = {0};
+       struct tee_ioctl_open_session_arg arg = {0};
+       uuid_t ta_mem_uuid;
+       int ret;
+
+       sec_heap->tee_ctx = tee_client_open_context(NULL, mtk_optee_ctx_match,
+                                                   NULL, NULL);
+       if (IS_ERR(sec_heap->tee_ctx)) {
+               pr_err("%s: open context failed, ret=%ld\n", sec_heap->name,
+                      PTR_ERR(sec_heap->tee_ctx));
+               return -ENODEV;
+       }
+
+       arg.num_params = MTK_TEE_PARAM_NUM;
+       arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
+       ret = uuid_parse(TZ_TA_MEM_UUID, &ta_mem_uuid);
+       if (ret)
+               goto close_context;
+       memcpy(&arg.uuid, &ta_mem_uuid.b, sizeof(ta_mem_uuid));
+
+       ret = tee_client_open_session(sec_heap->tee_ctx, &arg, t_param);
+       if (ret < 0 || arg.ret) {
+               pr_err("%s: open session failed, ret=%d:%d\n",
+                      sec_heap->name, ret, arg.ret);
+               ret = -EINVAL;
+               goto close_context;
+       }
+       sec_heap->mem_session = arg.session;
+       return 0;
+
+close_context:
+       tee_client_close_context(sec_heap->tee_ctx);
+       return ret;
+}
+
 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 *sec_heap = dma_heap_get_drvdata(heap);
        struct mtk_secure_heap_buffer *sec_buf;
        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
        struct dma_buf *dmabuf;
        int ret;
 
+       /*
+        * TEE probe may be late. Initialise the secure session in the first
+        * allocating secure buffer.
+        */
+       if (!sec_heap->mem_session) {
+               ret = mtk_kree_secure_session_init(sec_heap);
+               if (ret)
+                       return ERR_PTR(ret);
+       }
+
        sec_buf = kzalloc(sizeof(*sec_buf), GFP_KERNEL);
        if (!sec_buf)
                return ERR_PTR(-ENOMEM);
-- 
2.25.1