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0006 #include <linux/kernel.h>
0007 #include <linux/cdev.h>
0008 #include <linux/err.h>
0009 #include <linux/module.h>
0010 #include <linux/platform_device.h>
0011 #include <linux/of.h>
0012 #include <linux/of_reserved_mem.h>
0013 #include <linux/dma-mapping.h>
0014 #include <linux/slab.h>
0015 #include <linux/uaccess.h>
0016 #include <linux/io.h>
0017 #include <linux/qcom_scm.h>
0018
0019 #define QCOM_RMTFS_MEM_DEV_MAX (MINORMASK + 1)
0020
0021 static dev_t qcom_rmtfs_mem_major;
0022
0023 struct qcom_rmtfs_mem {
0024 struct device dev;
0025 struct cdev cdev;
0026
0027 void *base;
0028 phys_addr_t addr;
0029 phys_addr_t size;
0030
0031 unsigned int client_id;
0032
0033 unsigned int perms;
0034 };
0035
0036 static ssize_t qcom_rmtfs_mem_show(struct device *dev,
0037 struct device_attribute *attr,
0038 char *buf);
0039
0040 static DEVICE_ATTR(phys_addr, 0444, qcom_rmtfs_mem_show, NULL);
0041 static DEVICE_ATTR(size, 0444, qcom_rmtfs_mem_show, NULL);
0042 static DEVICE_ATTR(client_id, 0444, qcom_rmtfs_mem_show, NULL);
0043
0044 static ssize_t qcom_rmtfs_mem_show(struct device *dev,
0045 struct device_attribute *attr,
0046 char *buf)
0047 {
0048 struct qcom_rmtfs_mem *rmtfs_mem = container_of(dev,
0049 struct qcom_rmtfs_mem,
0050 dev);
0051
0052 if (attr == &dev_attr_phys_addr)
0053 return sprintf(buf, "%pa\n", &rmtfs_mem->addr);
0054 if (attr == &dev_attr_size)
0055 return sprintf(buf, "%pa\n", &rmtfs_mem->size);
0056 if (attr == &dev_attr_client_id)
0057 return sprintf(buf, "%d\n", rmtfs_mem->client_id);
0058
0059 return -EINVAL;
0060 }
0061
0062 static struct attribute *qcom_rmtfs_mem_attrs[] = {
0063 &dev_attr_phys_addr.attr,
0064 &dev_attr_size.attr,
0065 &dev_attr_client_id.attr,
0066 NULL
0067 };
0068 ATTRIBUTE_GROUPS(qcom_rmtfs_mem);
0069
0070 static int qcom_rmtfs_mem_open(struct inode *inode, struct file *filp)
0071 {
0072 struct qcom_rmtfs_mem *rmtfs_mem = container_of(inode->i_cdev,
0073 struct qcom_rmtfs_mem,
0074 cdev);
0075
0076 get_device(&rmtfs_mem->dev);
0077 filp->private_data = rmtfs_mem;
0078
0079 return 0;
0080 }
0081 static ssize_t qcom_rmtfs_mem_read(struct file *filp,
0082 char __user *buf, size_t count, loff_t *f_pos)
0083 {
0084 struct qcom_rmtfs_mem *rmtfs_mem = filp->private_data;
0085
0086 if (*f_pos >= rmtfs_mem->size)
0087 return 0;
0088
0089 if (*f_pos + count >= rmtfs_mem->size)
0090 count = rmtfs_mem->size - *f_pos;
0091
0092 if (copy_to_user(buf, rmtfs_mem->base + *f_pos, count))
0093 return -EFAULT;
0094
0095 *f_pos += count;
0096 return count;
0097 }
0098
0099 static ssize_t qcom_rmtfs_mem_write(struct file *filp,
0100 const char __user *buf, size_t count,
0101 loff_t *f_pos)
0102 {
0103 struct qcom_rmtfs_mem *rmtfs_mem = filp->private_data;
0104
0105 if (*f_pos >= rmtfs_mem->size)
0106 return 0;
0107
0108 if (*f_pos + count >= rmtfs_mem->size)
0109 count = rmtfs_mem->size - *f_pos;
0110
0111 if (copy_from_user(rmtfs_mem->base + *f_pos, buf, count))
0112 return -EFAULT;
0113
0114 *f_pos += count;
0115 return count;
0116 }
0117
0118 static int qcom_rmtfs_mem_release(struct inode *inode, struct file *filp)
0119 {
0120 struct qcom_rmtfs_mem *rmtfs_mem = filp->private_data;
0121
0122 put_device(&rmtfs_mem->dev);
0123
0124 return 0;
0125 }
0126
0127 static struct class rmtfs_class = {
0128 .owner = THIS_MODULE,
0129 .name = "rmtfs",
0130 };
0131
0132 static int qcom_rmtfs_mem_mmap(struct file *filep, struct vm_area_struct *vma)
0133 {
0134 struct qcom_rmtfs_mem *rmtfs_mem = filep->private_data;
0135
0136 if (vma->vm_end - vma->vm_start > rmtfs_mem->size) {
0137 dev_dbg(&rmtfs_mem->dev,
0138 "vm_end[%lu] - vm_start[%lu] [%lu] > mem->size[%pa]\n",
0139 vma->vm_end, vma->vm_start,
0140 (vma->vm_end - vma->vm_start), &rmtfs_mem->size);
0141 return -EINVAL;
0142 }
0143
0144 vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
0145 return remap_pfn_range(vma,
0146 vma->vm_start,
0147 rmtfs_mem->addr >> PAGE_SHIFT,
0148 vma->vm_end - vma->vm_start,
0149 vma->vm_page_prot);
0150 }
0151
0152 static const struct file_operations qcom_rmtfs_mem_fops = {
0153 .owner = THIS_MODULE,
0154 .open = qcom_rmtfs_mem_open,
0155 .read = qcom_rmtfs_mem_read,
0156 .write = qcom_rmtfs_mem_write,
0157 .release = qcom_rmtfs_mem_release,
0158 .llseek = default_llseek,
0159 .mmap = qcom_rmtfs_mem_mmap,
0160 };
0161
0162 static void qcom_rmtfs_mem_release_device(struct device *dev)
0163 {
0164 struct qcom_rmtfs_mem *rmtfs_mem = container_of(dev,
0165 struct qcom_rmtfs_mem,
0166 dev);
0167
0168 kfree(rmtfs_mem);
0169 }
0170
0171 static int qcom_rmtfs_mem_probe(struct platform_device *pdev)
0172 {
0173 struct device_node *node = pdev->dev.of_node;
0174 struct qcom_scm_vmperm perms[2];
0175 struct reserved_mem *rmem;
0176 struct qcom_rmtfs_mem *rmtfs_mem;
0177 u32 client_id;
0178 u32 vmid;
0179 int ret;
0180
0181 rmem = of_reserved_mem_lookup(node);
0182 if (!rmem) {
0183 dev_err(&pdev->dev, "failed to acquire memory region\n");
0184 return -EINVAL;
0185 }
0186
0187 ret = of_property_read_u32(node, "qcom,client-id", &client_id);
0188 if (ret) {
0189 dev_err(&pdev->dev, "failed to parse \"qcom,client-id\"\n");
0190 return ret;
0191
0192 }
0193
0194 rmtfs_mem = kzalloc(sizeof(*rmtfs_mem), GFP_KERNEL);
0195 if (!rmtfs_mem)
0196 return -ENOMEM;
0197
0198 rmtfs_mem->addr = rmem->base;
0199 rmtfs_mem->client_id = client_id;
0200 rmtfs_mem->size = rmem->size;
0201
0202 device_initialize(&rmtfs_mem->dev);
0203 rmtfs_mem->dev.parent = &pdev->dev;
0204 rmtfs_mem->dev.groups = qcom_rmtfs_mem_groups;
0205 rmtfs_mem->dev.release = qcom_rmtfs_mem_release_device;
0206
0207 rmtfs_mem->base = devm_memremap(&rmtfs_mem->dev, rmtfs_mem->addr,
0208 rmtfs_mem->size, MEMREMAP_WC);
0209 if (IS_ERR(rmtfs_mem->base)) {
0210 dev_err(&pdev->dev, "failed to remap rmtfs_mem region\n");
0211 ret = PTR_ERR(rmtfs_mem->base);
0212 goto put_device;
0213 }
0214
0215 cdev_init(&rmtfs_mem->cdev, &qcom_rmtfs_mem_fops);
0216 rmtfs_mem->cdev.owner = THIS_MODULE;
0217
0218 dev_set_name(&rmtfs_mem->dev, "qcom_rmtfs_mem%d", client_id);
0219 rmtfs_mem->dev.id = client_id;
0220 rmtfs_mem->dev.class = &rmtfs_class;
0221 rmtfs_mem->dev.devt = MKDEV(MAJOR(qcom_rmtfs_mem_major), client_id);
0222
0223 ret = cdev_device_add(&rmtfs_mem->cdev, &rmtfs_mem->dev);
0224 if (ret) {
0225 dev_err(&pdev->dev, "failed to add cdev: %d\n", ret);
0226 goto put_device;
0227 }
0228
0229 ret = of_property_read_u32(node, "qcom,vmid", &vmid);
0230 if (ret < 0 && ret != -EINVAL) {
0231 dev_err(&pdev->dev, "failed to parse qcom,vmid\n");
0232 goto remove_cdev;
0233 } else if (!ret) {
0234 if (!qcom_scm_is_available()) {
0235 ret = -EPROBE_DEFER;
0236 goto remove_cdev;
0237 }
0238
0239 perms[0].vmid = QCOM_SCM_VMID_HLOS;
0240 perms[0].perm = QCOM_SCM_PERM_RW;
0241 perms[1].vmid = vmid;
0242 perms[1].perm = QCOM_SCM_PERM_RW;
0243
0244 rmtfs_mem->perms = BIT(QCOM_SCM_VMID_HLOS);
0245 ret = qcom_scm_assign_mem(rmtfs_mem->addr, rmtfs_mem->size,
0246 &rmtfs_mem->perms, perms, 2);
0247 if (ret < 0) {
0248 dev_err(&pdev->dev, "assign memory failed\n");
0249 goto remove_cdev;
0250 }
0251 }
0252
0253 dev_set_drvdata(&pdev->dev, rmtfs_mem);
0254
0255 return 0;
0256
0257 remove_cdev:
0258 cdev_device_del(&rmtfs_mem->cdev, &rmtfs_mem->dev);
0259 put_device:
0260 put_device(&rmtfs_mem->dev);
0261
0262 return ret;
0263 }
0264
0265 static int qcom_rmtfs_mem_remove(struct platform_device *pdev)
0266 {
0267 struct qcom_rmtfs_mem *rmtfs_mem = dev_get_drvdata(&pdev->dev);
0268 struct qcom_scm_vmperm perm;
0269
0270 if (rmtfs_mem->perms) {
0271 perm.vmid = QCOM_SCM_VMID_HLOS;
0272 perm.perm = QCOM_SCM_PERM_RW;
0273
0274 qcom_scm_assign_mem(rmtfs_mem->addr, rmtfs_mem->size,
0275 &rmtfs_mem->perms, &perm, 1);
0276 }
0277
0278 cdev_device_del(&rmtfs_mem->cdev, &rmtfs_mem->dev);
0279 put_device(&rmtfs_mem->dev);
0280
0281 return 0;
0282 }
0283
0284 static const struct of_device_id qcom_rmtfs_mem_of_match[] = {
0285 { .compatible = "qcom,rmtfs-mem" },
0286 {}
0287 };
0288 MODULE_DEVICE_TABLE(of, qcom_rmtfs_mem_of_match);
0289
0290 static struct platform_driver qcom_rmtfs_mem_driver = {
0291 .probe = qcom_rmtfs_mem_probe,
0292 .remove = qcom_rmtfs_mem_remove,
0293 .driver = {
0294 .name = "qcom_rmtfs_mem",
0295 .of_match_table = qcom_rmtfs_mem_of_match,
0296 },
0297 };
0298
0299 static int __init qcom_rmtfs_mem_init(void)
0300 {
0301 int ret;
0302
0303 ret = class_register(&rmtfs_class);
0304 if (ret)
0305 return ret;
0306
0307 ret = alloc_chrdev_region(&qcom_rmtfs_mem_major, 0,
0308 QCOM_RMTFS_MEM_DEV_MAX, "qcom_rmtfs_mem");
0309 if (ret < 0) {
0310 pr_err("qcom_rmtfs_mem: failed to allocate char dev region\n");
0311 goto unregister_class;
0312 }
0313
0314 ret = platform_driver_register(&qcom_rmtfs_mem_driver);
0315 if (ret < 0) {
0316 pr_err("qcom_rmtfs_mem: failed to register rmtfs_mem driver\n");
0317 goto unregister_chrdev;
0318 }
0319
0320 return 0;
0321
0322 unregister_chrdev:
0323 unregister_chrdev_region(qcom_rmtfs_mem_major, QCOM_RMTFS_MEM_DEV_MAX);
0324 unregister_class:
0325 class_unregister(&rmtfs_class);
0326 return ret;
0327 }
0328 module_init(qcom_rmtfs_mem_init);
0329
0330 static void __exit qcom_rmtfs_mem_exit(void)
0331 {
0332 platform_driver_unregister(&qcom_rmtfs_mem_driver);
0333 unregister_chrdev_region(qcom_rmtfs_mem_major, QCOM_RMTFS_MEM_DEV_MAX);
0334 class_unregister(&rmtfs_class);
0335 }
0336 module_exit(qcom_rmtfs_mem_exit);
0337
0338 MODULE_AUTHOR("Linaro Ltd");
0339 MODULE_DESCRIPTION("Qualcomm Remote Filesystem memory driver");
0340 MODULE_LICENSE("GPL v2");
