bsp: k230: add mem device

Provide mem devices to facilitate the user layer to directly map physical
addresses to virtual addresses through ioctrl, mainly to accelerate data
access during image processing.

Signed-off-by: Wang Chen <[email protected]>

Author: unicornx

bsp/k230/drivers/extcomponents/dev_mem/SConscript

@@ -0,0 +1,19 @@
+# RT-Thread building script for component
+
+from building import *
+
+cwd     = GetCurrentDir()
+src     = Glob('*.c')
+CPPPATH = [cwd]
+
+group = DefineGroup('dev_mem', src, depend = ['RT_USING_DEVMEM'], CPPPATH = CPPPATH)
+
+objs = [group]
+
+list = os.listdir(cwd)
+
+for item in list:
+    if os.path.isfile(os.path.join(cwd, item, 'SConscript')):
+        objs = objs + SConscript(os.path.join(item, 'SConscript'))
+
+Return('objs')

bsp/k230/drivers/extcomponents/dev_mem/rt_dev_mem.c

@@ -0,0 +1,79 @@
+/**
+ * @file rt_mem.c
+ * @author
+ * @brief
+ * @version 1.0
+ * @date 2022-10-25
+ *
+ * @copyright Copyright (c) 2022 Canaan Inc.
+ *
+ */
+#include <time.h>
+#include <string.h>
+#include <rtthread.h>
+#include <dfs_file.h>
+#include "lwp_user_mm.h"
+
+#ifndef PAGE_OFFSET_BIT
+#define PAGE_OFFSET_BIT     12
+#endif
+
+static struct rt_device mem_dev;
+
+static int mem_open(struct dfs_file *file)
+{
+    return 0;
+}
+
+static int mem_close(struct dfs_file *file)
+{
+    return 0;
+}
+
+static int mem_ioctl(struct dfs_file *file, int cmd, void *args)
+{
+    struct dfs_mmap2_args *mmap_args;
+    unsigned long offset;
+    int cached = 1;
+
+    if(cmd != RT_FIOMMAP2)
+        return RT_EOK;
+
+    if(file->flags & O_SYNC)
+        cached = 0;
+
+    mmap_args = (struct dfs_mmap2_args *)(args);
+    offset = mmap_args->pgoffset << PAGE_OFFSET_BIT;
+    void *mmap_addr;
+
+    mmap_addr = lwp_map_user_phy(lwp_self(), RT_NULL,
+                                (void *)(size_t)(mmap_args->pgoffset << PAGE_OFFSET_BIT),
+                                mmap_args->length, cached);
+    mmap_args->ret = mmap_addr;
+
+    return 0;
+}
+
+static const struct dfs_file_ops mem_fops = {
+    .open = mem_open,
+    .close = mem_close,
+    .ioctl = mem_ioctl,
+};
+
+
+int mem_device_init(void)
+{
+    RT_ASSERT(!rt_device_find("mem"));
+    mem_dev.type    = RT_Device_Class_Miscellaneous;
+
+    /* no private */
+    mem_dev.user_data = RT_NULL;
+
+    rt_device_register(&mem_dev, "mem", RT_DEVICE_FLAG_RDWR);
+
+    mem_dev.fops = &mem_fops;
+
+    return 0;
+}
+INIT_DEVICE_EXPORT(mem_device_init);
+