dm: prepare vSSRAM buffers

This patch allocates cache buffers from native TCC
 buffer driver and do setup, make them  ready to be
 mapped to ACRN user VMs as software  SRAM regions.

Tracked-On: #7010
Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>
Acked-by: Yu1 Wang <yu1.wang@intel.com>

devicemodel/hw/platform/vssram/vssram.c

@@ -10,6 +10,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/user.h>
+#include <sys/mman.h>
 #include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -209,6 +210,58 @@ static int tcc_driver_get_memory_config(int region_id, struct tcc_mem_region_con
 	return 0;
 }
 
+/**
+ * @brief  Request TCC software SRAM buffer from region specified by region ID.
+ *
+ * @param region_id  Target software SRAM region ID.
+ * @param size       Request buffer size in bytes.
+ *
+ * @return device node ID on success and -1 on fail.
+ */
+static int tcc_driver_req_buffer(unsigned int region_id, unsigned int size)
+{
+	struct tcc_buf_mem_req req;
+
+	memset(&req, 0, sizeof(req));
+	req.devnode_id = -1;
+	req.id = region_id;
+	req.size = size;
+
+	if (ioctl(tcc_buffer_fd, TCC_REQ_BUFFER, &req) < 0) {
+		pr_err("%s failed: fd=%d, region_id=%u, size=%ld KB.\n",
+			__func__, tcc_buffer_fd, req.id, req.size);
+		return -1;
+	}
+
+	pr_info("%s succ: region_id: %d, size: %ld KB, dev_node=%d.\n",
+		__func__, region_id, req.size >> 10, req.devnode_id);
+
+	return (int)req.devnode_id;
+}
+
+/**
+ * @brief  Get file descriptor handler to TCC cache buffer.
+ *
+ * @param devnode_id  Device node ID of TCC buffer.
+ *
+ * @return         File descriptor on success and -1 on fail.
+ */
+static int vssram_open_buffer(int devnode_id)
+{
+	int fd;
+	char buffer_file_name[256];
+
+	sprintf(buffer_file_name, "%s%i", TCC_BUFFER_DEVNODE, devnode_id);
+
+	fd = open(buffer_file_name, O_RDWR);
+	if (fd == INVALID_FD) {
+		pr_err("%s, Failure open('%s', O_RDRW):error: %s(%i)",
+			__func__, buffer_file_name, strerror(errno), errno);
+	}
+
+	return fd;
+}
+
 /**
  * @brief Release all vSSRAM buffers and close file
  *        descriptors of TCC cache buffers.
@@ -219,7 +272,45 @@ static int tcc_driver_get_memory_config(int region_id, struct tcc_mem_region_con
  */
 static void vssram_close_buffers(void)
 {
-	/* to be implemented */
+	int i;
+	struct vssram_buf *vbuf;
+
+	if (!vssram_buffers)
+		return;
+
+	for (i = 0; i < MAX_VSSRAM_BUFFER_NUM; i++) {
+		vbuf = &vssram_buffers[i];
+		if (vbuf->fd != -1) {
+			munmap((void *)vbuf->vma_base, vbuf->size);
+			close(vbuf->fd);
+		}
+	}
+
+	if (tcc_buffer_fd != INVALID_FD) {
+		close(tcc_buffer_fd);
+		tcc_buffer_fd = INVALID_FD;
+	}
+}
+
+/**
+ * @brief        Creates a memory mapping for cache buffer.
+ *
+ * @param fd     File descriptor of cache buffer device node.
+ * @param size   Size of cache buffer
+ *
+ * @return       Pointer to the mapped area on success and NULL on fail.
+ */
+static void *vssram_mmap_buffer(int fd, size_t size)
+{
+	void *memory;
+
+	memory = mmap(NULL, size, 0, MAP_FILE | MAP_SHARED, fd, 0);
+	if (memory == MAP_FAILED) {
+		pr_err("%s, Failure mmap on fd:%d, size:%ld.\n", __func__, fd, size);
+		return NULL;
+	}
+
+	return memory;
 }
 
 static int init_guest_lapicid_tbl(struct acrn_platform_info *platform_info, uint64_t guest_pcpu_bitmask)
@@ -486,6 +577,118 @@ err:
 	return -1;
 }
 
+/**
+ * @brief  Request cache buffer based on the TCC software SRAM regions configurations.
+ *
+ * @param vbuf     Pointer to cache buffer description.
+ * @param mem_info Pointer to memory region configurations .
+ *
+ * @return device node of cache buffer on success and -1 on fail.
+ */
+static int vssram_request_buffer(struct vssram_buf *vbuf,
+		struct tcc_memory_info *mem_info)
+{
+	int i, pcpuid = 0, devnode_id = -1;
+	struct tcc_mem_region_config *config;
+
+	if (CPU_COUNT(&vbuf->pcpumask) == 0) {
+		pr_err("%s pCPU mask is not configured in cache buffer description.\n", __func__);
+		return -1;
+	}
+
+	/* get pCPU ID that has affinity with current cache buffer, use 0 for L3 cache buffer,
+	 * all CPUs in this pcpumask can access current cache buffer, so select anyone inside.
+	 */
+	for (pcpuid = 0; pcpuid < ACRN_PLATFORM_LAPIC_IDS_MAX; pcpuid++) {
+		if (CPU_ISSET(pcpuid, &vbuf->pcpumask))
+			break;
+	}
+	assert((pcpuid > 0) && (pcpuid < ACRN_PLATFORM_LAPIC_IDS_MAX));
+
+	/* Request cache buffer from TCC kernel driver */
+	for (i = 0; i < mem_info->region_cnt; i++) {
+		config = mem_info->region_configs + i;
+		if (CPU_ISSET(pcpuid, (cpu_set_t *)config->cpu_mask_p)
+			&& (config->size >= vbuf->size)
+			&& (config->type == vbuf->level)) {
+			devnode_id = tcc_driver_req_buffer(i, vbuf->size);
+			if (devnode_id > 0) {
+				vbuf->waymask = config->ways;
+				break;
+			}
+		}
+	}
+	return devnode_id;
+}
+
+/**
+ * @brief  Allocate cache buffer from TCC software SRAM regions
+ *         and setup memory mapping.
+ *
+ * @param vbuf     Pointer to cache buffer description.
+ * @param mem_info Pointer to memory region configurations .
+ *
+ * @return 0 on success and -1 on fail.
+ */
+static int vssram_setup_buffer(struct vssram_buf *vbuf,
+		struct tcc_memory_info *mem_info)
+{
+	void *ptr;
+	int devnode_id, fd;
+
+	devnode_id = vssram_request_buffer(vbuf, mem_info);
+	if (devnode_id == -1) {
+		pr_err("%s, request buffer failed, size:%x.\n",
+			__func__, vbuf->size);
+		return -1;
+	}
+
+	fd = vssram_open_buffer(devnode_id);
+	if (fd == INVALID_FD) {
+		pr_err("%s, open buffer device node(%d) failed.\n", __func__, devnode_id);
+		return -1;
+	}
+
+	ptr = vssram_mmap_buffer(fd, vbuf->size);
+	if (ptr == NULL) {
+		pr_err("%s, mmap buffer failed, devnode_id:%.\n", __func__, devnode_id);
+		return -1;
+	}
+
+	vbuf->vma_base = (uint64_t)ptr;
+	vbuf->fd = fd;
+	return 0;
+}
+
+/**
+ * @brief  Prepare cache buffers according the cache buffer descriptions.
+ *
+ * @param mem_info Pointer to memory region configurations.
+ *
+ * @return 0 on success and -1 on fail.
+ *
+ * @pre vssram_buffers != NULL
+ */
+static int vssram_prepare_buffers(struct tcc_memory_info *mem_info)
+{
+	int i;
+	struct vssram_buf *vbuf;
+
+	for (i = 0; i < MAX_VSSRAM_BUFFER_NUM; i++) {
+		vbuf = &vssram_buffers[i];
+
+		if (vbuf->size == 0)
+			break;
+
+		if (vssram_setup_buffer(vbuf, mem_info) < 0) {
+			pr_err("%s, allocate cache(level:%d, size:%x) failed\n",
+				__func__, vbuf->level, vbuf->size);
+			return -1;
+		}
+	}
+	return 0;
+}
+
 /**
  * @brief  Initialize L2 & L3 vSSRAM buffer context table.
  *
@@ -669,6 +872,11 @@ int init_vssram(struct vmctx *ctx)
 		goto exit;
 	}
 
+	if (vssram_prepare_buffers(&mem_info) < 0) {
+		pr_err("%s, prepare vssram buffers failed.\n", __func__);
+		goto exit;
+	}
+
 exit:
 	if (mem_info.region_configs)
 		free(mem_info.region_configs);