dsa: mv88x6xxx: Add debugfs interface for scratch registers

Allow the contents of the scratch registers to be shown in debugfs.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/dsa/mv88e6xxx.c b/drivers/net/dsa/mv88e6xxx.c
index 7e12a31..c938d7c 100644 (file)
--- a/drivers/net/dsa/mv88e6xxx.c
+++ b/drivers/net/dsa/mv88e6xxx.c
@@ -901,6 +901,13 @@ static int _mv88e6xxx_atu_wait(struct dsa_switch *ds)
                               GLOBAL_ATU_OP_BUSY);
 }
 
+/* Must be called with SMI lock held */
+static int _mv88e6xxx_scratch_wait(struct dsa_switch *ds)
+{
+       return _mv88e6xxx_wait(ds, REG_GLOBAL2, GLOBAL2_SCRATCH_MISC,
+                              GLOBAL2_SCRATCH_BUSY);
+}
+
 /* Must be called with SMI mutex held */
 static int _mv88e6xxx_phy_read_indirect(struct dsa_switch *ds, int addr,
                                        int regnum)
@@ -1825,6 +1832,50 @@ static const struct file_operations mv88e6xxx_device_map_fops = {
        .owner  = THIS_MODULE,
 };
 
+static int mv88e6xxx_scratch_show(struct seq_file *s, void *p)
+{
+       struct dsa_switch *ds = s->private;
+       struct mv88e6xxx_priv_state *ps = ds_to_priv(ds);
+       int reg, ret;
+
+       seq_puts(s, "Register Value\n");
+
+       mutex_lock(&ps->smi_mutex);
+       for (reg = 0; reg < 0x80; reg++) {
+               ret = _mv88e6xxx_reg_write(
+                       ds, REG_GLOBAL2, GLOBAL2_SCRATCH_MISC,
+                       reg << GLOBAL2_SCRATCH_REGISTER_SHIFT);
+               if (ret < 0)
+                       goto out;
+
+               ret = _mv88e6xxx_scratch_wait(ds);
+               if (ret < 0)
+                       goto out;
+
+               ret = _mv88e6xxx_reg_read(ds, REG_GLOBAL2,
+                                         GLOBAL2_SCRATCH_MISC);
+               seq_printf(s, "  %2x   %2x\n", reg,
+                          ret & GLOBAL2_SCRATCH_VALUE_MASK);
+       }
+out:
+       mutex_unlock(&ps->smi_mutex);
+
+       return 0;
+}
+
+static int mv88e6xxx_scratch_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, mv88e6xxx_scratch_show, inode->i_private);
+}
+
+static const struct file_operations mv88e6xxx_scratch_fops = {
+       .open   = mv88e6xxx_scratch_open,
+       .read   = seq_read,
+       .llseek = no_llseek,
+       .release = single_release,
+       .owner  = THIS_MODULE,
+};
+
 int mv88e6xxx_setup_common(struct dsa_switch *ds)
 {
        struct mv88e6xxx_priv_state *ps = ds_to_priv(ds);
@@ -1853,6 +1904,9 @@ int mv88e6xxx_setup_common(struct dsa_switch *ds)
 
        debugfs_create_file("device_map", S_IRUGO, ps->dbgfs, ds,
                            &mv88e6xxx_device_map_fops);
+
+       debugfs_create_file("scratch", S_IRUGO, ps->dbgfs, ds,
+                           &mv88e6xxx_scratch_fops);
        return 0;
 }
 

diff --git a/drivers/net/dsa/mv88e6xxx.h b/drivers/net/dsa/mv88e6xxx.h
index a2c9ac0..a650b26 100644 (file)
--- a/drivers/net/dsa/mv88e6xxx.h
+++ b/drivers/net/dsa/mv88e6xxx.h
@@ -297,6 +297,9 @@
 #define GLOBAL2_SMI_OP_45_READ_DATA    ((2 << 10) | GLOBAL2_SMI_OP_BUSY)
 #define GLOBAL2_SMI_DATA       0x19
 #define GLOBAL2_SCRATCH_MISC   0x1a
+#define GLOBAL2_SCRATCH_BUSY           BIT(15)
+#define GLOBAL2_SCRATCH_REGISTER_SHIFT 8
+#define GLOBAL2_SCRATCH_VALUE_MASK     0xff
 #define GLOBAL2_WDOG_CONTROL   0x1b
 #define GLOBAL2_QOS_WEIGHT     0x1c
 #define GLOBAL2_MISC           0x1d