diff options
Diffstat (limited to 'arch/powerpc/platforms/powernv/opal-lpc.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/opal-lpc.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/opal-lpc.c b/arch/powerpc/platforms/powernv/opal-lpc.c index 79d83cad3d67..70eff22aef73 100644 --- a/arch/powerpc/platforms/powernv/opal-lpc.c +++ b/arch/powerpc/platforms/powernv/opal-lpc.c @@ -12,12 +12,16 @@ #include <linux/kernel.h> #include <linux/of.h> #include <linux/bug.h> +#include <linux/debugfs.h> +#include <linux/io.h> +#include <linux/slab.h> #include <asm/machdep.h> #include <asm/firmware.h> #include <asm/xics.h> #include <asm/opal.h> #include <asm/prom.h> +#include <asm/uaccess.h> static int opal_lpc_chip_id = -1; @@ -176,6 +180,152 @@ static const struct ppc_pci_io opal_lpc_io = { .outsl = opal_lpc_outsl, }; +#ifdef CONFIG_DEBUG_FS +struct lpc_debugfs_entry { + enum OpalLPCAddressType lpc_type; +}; + +static ssize_t lpc_debug_read(struct file *filp, char __user *ubuf, + size_t count, loff_t *ppos) +{ + struct lpc_debugfs_entry *lpc = filp->private_data; + u32 data, pos, len, todo; + int rc; + + if (!access_ok(VERIFY_WRITE, ubuf, count)) + return -EFAULT; + + todo = count; + while (todo) { + pos = *ppos; + + /* + * Select access size based on count and alignment and + * access type. IO and MEM only support byte acceses, + * FW supports all 3. + */ + len = 1; + if (lpc->lpc_type == OPAL_LPC_FW) { + if (todo > 3 && (pos & 3) == 0) + len = 4; + else if (todo > 1 && (pos & 1) == 0) + len = 2; + } + rc = opal_lpc_read(opal_lpc_chip_id, lpc->lpc_type, pos, + &data, len); + if (rc) + return -ENXIO; + switch(len) { + case 4: + rc = __put_user((u32)data, (u32 __user *)ubuf); + break; + case 2: + rc = __put_user((u16)data, (u16 __user *)ubuf); + break; + default: + rc = __put_user((u8)data, (u8 __user *)ubuf); + break; + } + if (rc) + return -EFAULT; + *ppos += len; + ubuf += len; + todo -= len; + } + + return count; +} + +static ssize_t lpc_debug_write(struct file *filp, const char __user *ubuf, + size_t count, loff_t *ppos) +{ + struct lpc_debugfs_entry *lpc = filp->private_data; + u32 data, pos, len, todo; + int rc; + + if (!access_ok(VERIFY_READ, ubuf, count)) + return -EFAULT; + + todo = count; + while (todo) { + pos = *ppos; + + /* + * Select access size based on count and alignment and + * access type. IO and MEM only support byte acceses, + * FW supports all 3. + */ + len = 1; + if (lpc->lpc_type == OPAL_LPC_FW) { + if (todo > 3 && (pos & 3) == 0) + len = 4; + else if (todo > 1 && (pos & 1) == 0) + len = 2; + } + switch(len) { + case 4: + rc = __get_user(data, (u32 __user *)ubuf); + break; + case 2: + rc = __get_user(data, (u16 __user *)ubuf); + break; + default: + rc = __get_user(data, (u8 __user *)ubuf); + break; + } + if (rc) + return -EFAULT; + + rc = opal_lpc_write(opal_lpc_chip_id, lpc->lpc_type, pos, + data, len); + if (rc) + return -ENXIO; + *ppos += len; + ubuf += len; + todo -= len; + } + + return count; +} + +static const struct file_operations lpc_fops = { + .read = lpc_debug_read, + .write = lpc_debug_write, + .open = simple_open, + .llseek = default_llseek, +}; + +static int opal_lpc_debugfs_create_type(struct dentry *folder, + const char *fname, + enum OpalLPCAddressType type) +{ + struct lpc_debugfs_entry *entry; + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; + entry->lpc_type = type; + debugfs_create_file(fname, 0600, folder, entry, &lpc_fops); + return 0; +} + +static int opal_lpc_init_debugfs(void) +{ + struct dentry *root; + int rc = 0; + + if (opal_lpc_chip_id < 0) + return -ENODEV; + + root = debugfs_create_dir("lpc", powerpc_debugfs_root); + + rc |= opal_lpc_debugfs_create_type(root, "io", OPAL_LPC_IO); + rc |= opal_lpc_debugfs_create_type(root, "mem", OPAL_LPC_MEM); + rc |= opal_lpc_debugfs_create_type(root, "fw", OPAL_LPC_FW); + return rc; +} +device_initcall(opal_lpc_init_debugfs); +#endif /* CONFIG_DEBUG_FS */ + void opal_lpc_init(void) { struct device_node *np; |