...

study/driver/cma/.cma.ko.cmd

@@ -0,0 +1 @@
+cmd_/home/gatieme/Work/GitHub/LDD-LinuxDeviceDrivers/study/driver/cma/cma.ko := aarch64-linux-gnu-ld -EL -r  -T /usr/src/linux-headers-3.14.0-20150821.kylin.3.desktop/scripts/module-common.lds --build-id  -o /home/gatieme/Work/GitHub/LDD-LinuxDeviceDrivers/study/driver/cma/cma.ko /home/gatieme/Work/GitHub/LDD-LinuxDeviceDrivers/study/driver/cma/cma.o /home/gatieme/Work/GitHub/LDD-LinuxDeviceDrivers/study/driver/cma/cma.mod.o

study/driver/cma/.tmp_versions/cma.mod

@@ -0,0 +1,2 @@
+/home/gatieme/Work/GitHub/LDD-LinuxDeviceDrivers/study/driver/cma/cma.ko
+/home/gatieme/Work/GitHub/LDD-LinuxDeviceDrivers/study/driver/cma/cma.o

study/driver/cma/Makefile

@@ -0,0 +1,80 @@
+# ------------------------------------------------------------------------------
+#
+# Makefile for the LDD-LinuxDeviceDrivers.
+#
+# Author: gatieme
+# Create: 2016-07-29 15:50:46
+# Last modified: 2016-07-29 16:10:29
+# Description:
+# 	This program is loaded as a kernel(v2.6.18 or later) module.
+# 	Use "make install" to load it into kernel.
+# 	Use "make remove" to remove the module out of kernel.
+#
+# ------------------------------------------------------------------------------
+
+
+ROOT=../../../../../
+#PLATFORM=$(shell $(ROOT)/systype.sh)
+#include $(ROOT)/Make.defines.$(PLATFORM)
+
+#	my driver description
+DRIVER_VERSION := "1.0.0"
+DRIVER_AUTHOR  := "Gatieme @ AderStep Inc..."
+DRIVER_DESC    := "Demo module for LDD-LinuxDeviceDrivers devices"
+DRIVER_LICENSE := "Dual BSD/GPL"
+
+DEV_FILE	:= /dev/cmd_test
+MODULE_NAME := cma
+
+ifneq ($(KERNELRELEASE),)
+
+#CFG_FLAGS += -O2  -I./
+#EXTRA_CFLAGS  += $(C_FLAGS) $(CFG_INC) $(CFG_INC)
+
+
+
+obj-m := $(MODULE_NAME).o #smodule.o
+
+else
+
+KERNELDIR ?= /lib/modules/$(shell uname -r)/build
+
+PWD := $(shell pwd)
+
+modules:
+	make -C $(KERNELDIR) M=$(PWD) modules
+
+modules_install:
+	make -C $(KERNELDIR) M=$(PWD) modules_install
+
+
+
+insmod:
+	sudo insmod $(MODULE_NAME).ko
+#sudo mknod $(DEV_FILE) c 224 0
+
+reinsmod:
+	sudo rmmod $(MODULE_NAME)
+	sudo insmod $(MODULE_NAME).ko
+
+rmmod:
+	sudo rmmod $(MODULE_NAME)
+	sudo /bin/rm $(DEV_FILE)
+
+clean:
+	make -C $(KERNELDIR) M=$(PWD) clean
+	rm -f modules.order Module.symvers Module.markers
+
+
+COMMIT="[1.1.4 带参数的可加载模块](http://book.51cto.com/art/201205/337663.htm)"
+github:
+	cd $(ROOT) && make github
+
+
+.PHNOY:
+	modules modules_install clean
+
+
+
+endif
+

study/driver/cma/cma.c

@@ -0,0 +1,106 @@
+/* 
+ * kernel module helper for testing CMA 
+ * 
+ * Licensed under GPLv2 or later. 
+ */  
+  
+#include <linux/module.h>   
+#include <linux/device.h>   
+#include <linux/fs.h>   
+#include <linux/miscdevice.h>   
+#include <linux/dma-mapping.h>   
+  
+#define CMA_NUM  10   
+static struct device *cma_dev;  
+static dma_addr_t dma_phys[CMA_NUM];  
+static void *dma_virt[CMA_NUM];  
+  
+/* any read request will free coherent memory, eg. 
+ * cat /dev/cma_test 
+ */  
+static ssize_t  
+cma_test_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)  
+{  
+    int i;  
+  
+    for (i = 0; i < CMA_NUM; i++) {  
+        if (dma_virt[i]) {  
+            dma_free_coherent(cma_dev, (i + 1) * SZ_1M, dma_virt[i], dma_phys[i]);  
+            _dev_info(cma_dev, "free virt: %p phys: %p\n", dma_virt[i], (void *)dma_phys[i]);  
+            dma_virt[i] = NULL;  
+            break;  
+        }  
+    }  
+    return 0;  
+}  
+  
+/* 
+ * any write request will alloc coherent memory, eg. 
+ * echo 0 > /dev/cma_test 
+ */  
+static ssize_t  
+cma_test_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)  
+{  
+    int i;  
+    int ret;  
+  
+    for (i = 0; i < CMA_NUM; i++) {  
+        if (!dma_virt[i]) {  
+            dma_virt[i] = dma_alloc_coherent(cma_dev, (i + 1) * SZ_1M, &dma_phys[i], GFP_KERNEL);  
+  
+            if (dma_virt[i]) {  
+                void *p;  
+                /* touch every page in the allocated memory */  
+                for (p = dma_virt[i]; p <  dma_virt[i] + (i + 1) * SZ_1M; p += PAGE_SIZE)  
+                    *(u32 *)p = 0;  
+  
+                _dev_info(cma_dev, "alloc virt: %p phys: %p\n", dma_virt[i], (void *)dma_phys[i]);  
+            } else {  
+                dev_err(cma_dev, "no mem in CMA area\n");  
+                ret = -ENOMEM;  
+            }  
+            break;  
+        }  
+    }  
+  
+    return count;  
+}  
+  
+static const struct file_operations cma_test_fops = {  
+    .owner =    THIS_MODULE,  
+    .read  =    cma_test_read,  
+    .write =    cma_test_write,  
+};  
+  
+static struct miscdevice cma_test_misc = {  
+    .name = "cma_test",  
+    .fops = &cma_test_fops,  
+};  
+  
+static int __init cma_test_init(void)  
+{  
+    int ret = 0;  
+  
+    ret = misc_register(&cma_test_misc);  
+    if (unlikely(ret)) {  
+        pr_err("failed to register cma test misc device!\n");  
+        return ret;  
+    }  
+    cma_dev = cma_test_misc.this_device;  
+    cma_dev->coherent_dma_mask = ~0;  
+    _dev_info(cma_dev, "registered.\n");  
+  
+    return ret;  
+}  
+module_init(cma_test_init);  
+  
+static void __exit cma_test_exit(void)  
+{  
+    misc_deregister(&cma_test_misc);  
+}  
+module_exit(cma_test_exit);  
+  
+MODULE_LICENSE("GPL");  
+MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");  
+MODULE_DESCRIPTION("kernel module to help the test of CMA");  
+MODULE_ALIAS("CMA test");  

study/driver/cma/cma.mod.c

@@ -0,0 +1,35 @@
+#include <linux/module.h>
+#include <linux/vermagic.h>
+#include <linux/compiler.h>
+
+MODULE_INFO(vermagic, VERMAGIC_STRING);
+
+__visible struct module __this_module
+__attribute__((section(".gnu.linkonce.this_module"))) = {
+	.name = KBUILD_MODNAME,
+	.init = init_module,
+#ifdef CONFIG_MODULE_UNLOAD
+	.exit = cleanup_module,
+#endif
+	.arch = MODULE_ARCH_INIT,
+};
+
+static const struct modversion_info ____versions[]
+__used
+__attribute__((section("__versions"))) = {
+	{ 0x146be775, __VMLINUX_SYMBOL_STR(module_layout) },
+	{ 0x15625c2c, __VMLINUX_SYMBOL_STR(misc_deregister) },
+	{ 0x27e1a049, __VMLINUX_SYMBOL_STR(printk) },
+	{ 0x4bc5f446, __VMLINUX_SYMBOL_STR(misc_register) },
+	{ 0x92c17db0, __VMLINUX_SYMBOL_STR(dma_release_from_coherent) },
+	{ 0xf19146ad, __VMLINUX_SYMBOL_STR(dev_err) },
+	{ 0xd6b7c3a5, __VMLINUX_SYMBOL_STR(dma_ops) },
+	{ 0x9134613b, __VMLINUX_SYMBOL_STR(_dev_info) },
+	{ 0xc31e44bc, __VMLINUX_SYMBOL_STR(dma_alloc_from_coherent) },
+};
+
+static const char __module_depends[]
+__used
+__attribute__((section(".modinfo"))) =
+"depends=";
+

study/driver/cma/modules.order

@@ -0,0 +1 @@
+kernel//home/gatieme/Work/GitHub/LDD-LinuxDeviceDrivers/study/driver/cma/cma.ko