memory: emif: add debugfs entries for emif

Add debug entries for:
	1. calculated registers per frequency
	2. last polled value of MR4(temperature level
	   of LPDDR2 memory)

Signed-off-by: Aneesh V <aneesh@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Benoit Cousson <b-cousson@ti.com>
[santosh.shilimkar@ti.com: Moved to drivers/memory from drivers/misc]
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 138 insertions, 0 deletions

diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
index 3dfffbb8ab40..33a4396b24cb 100644
--- a/drivers/memory/emif.c
+++ b/drivers/memory/emif.c
@@ -18,6 +18,7 @@
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
 #include <linux/slab.h>
+#include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/module.h>
 #include <linux/list.h>
@@ -47,6 +48,7 @@
  *                              frequency change (i.e. corresponding to the
  *                              frequency in effect at the moment)
  * @plat_data:                  Pointer to saved platform data.
+ * @debugfs_root:               dentry to the root folder for EMIF in debugfs
  */
 struct emif_data {
         u8                              duplicate;
@@ -60,6 +62,7 @@ struct emif_data {
         struct emif_regs                *regs_cache[EMIF_MAX_NUM_FREQUENCIES];
         struct emif_regs                *curr_regs;
         struct emif_platform_data       *plat_data;
+        struct dentry                   *debugfs_root;
 };
 
 static struct emif_data *emif1;
@@ -68,6 +71,130 @@ static unsigned long	irq_state;
 static u32              t_ck; /* DDR clock period in ps */
 static LIST_HEAD(device_list);
 
+static void do_emif_regdump_show(struct seq_file *s, struct emif_data *emif,
+        struct emif_regs *regs)
+{
+        u32 type = emif->plat_data->device_info->type;
+        u32 ip_rev = emif->plat_data->ip_rev;
+
+        seq_printf(s, "EMIF register cache dump for %dMHz\n",
+                regs->freq/1000000);
+
+        seq_printf(s, "ref_ctrl_shdw\t: 0x%08x\n", regs->ref_ctrl_shdw);
+        seq_printf(s, "sdram_tim1_shdw\t: 0x%08x\n", regs->sdram_tim1_shdw);
+        seq_printf(s, "sdram_tim2_shdw\t: 0x%08x\n", regs->sdram_tim2_shdw);
+        seq_printf(s, "sdram_tim3_shdw\t: 0x%08x\n", regs->sdram_tim3_shdw);
+
+        if (ip_rev == EMIF_4D) {
+                seq_printf(s, "read_idle_ctrl_shdw_normal\t: 0x%08x\n",
+                        regs->read_idle_ctrl_shdw_normal);
+                seq_printf(s, "read_idle_ctrl_shdw_volt_ramp\t: 0x%08x\n",
+                        regs->read_idle_ctrl_shdw_volt_ramp);
+        } else if (ip_rev == EMIF_4D5) {
+                seq_printf(s, "dll_calib_ctrl_shdw_normal\t: 0x%08x\n",
+                        regs->dll_calib_ctrl_shdw_normal);
+                seq_printf(s, "dll_calib_ctrl_shdw_volt_ramp\t: 0x%08x\n",
+                        regs->dll_calib_ctrl_shdw_volt_ramp);
+        }
+
+        if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
+                seq_printf(s, "ref_ctrl_shdw_derated\t: 0x%08x\n",
+                        regs->ref_ctrl_shdw_derated);
+                seq_printf(s, "sdram_tim1_shdw_derated\t: 0x%08x\n",
+                        regs->sdram_tim1_shdw_derated);
+                seq_printf(s, "sdram_tim3_shdw_derated\t: 0x%08x\n",
+                        regs->sdram_tim3_shdw_derated);
+        }
+}
+
+static int emif_regdump_show(struct seq_file *s, void *unused)
+{
+        struct emif_data        *emif   = s->private;
+        struct emif_regs        **regs_cache;
+        int                     i;
+
+        if (emif->duplicate)
+                regs_cache = emif1->regs_cache;
+        else
+                regs_cache = emif->regs_cache;
+
+        for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
+                do_emif_regdump_show(s, emif, regs_cache[i]);
+                seq_printf(s, "\n");
+        }
+
+        return 0;
+}
+
+static int emif_regdump_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, emif_regdump_show, inode->i_private);
+}
+
+static const struct file_operations emif_regdump_fops = {
+        .open                   = emif_regdump_open,
+        .read                   = seq_read,
+        .release                = single_release,
+};
+
+static int emif_mr4_show(struct seq_file *s, void *unused)
+{
+        struct emif_data *emif = s->private;
+
+        seq_printf(s, "MR4=%d\n", emif->temperature_level);
+        return 0;
+}
+
+static int emif_mr4_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, emif_mr4_show, inode->i_private);
+}
+
+static const struct file_operations emif_mr4_fops = {
+        .open                   = emif_mr4_open,
+        .read                   = seq_read,
+        .release                = single_release,
+};
+
+static int __init_or_module emif_debugfs_init(struct emif_data *emif)
+{
+        struct dentry   *dentry;
+        int             ret;
+
+        dentry = debugfs_create_dir(dev_name(emif->dev), NULL);
+        if (IS_ERR(dentry)) {
+                ret = PTR_ERR(dentry);
+                goto err0;
+        }
+        emif->debugfs_root = dentry;
+
+        dentry = debugfs_create_file("regcache_dump", S_IRUGO,
+                        emif->debugfs_root, emif, &emif_regdump_fops);
+        if (IS_ERR(dentry)) {
+                ret = PTR_ERR(dentry);
+                goto err1;
+        }
+
+        dentry = debugfs_create_file("mr4", S_IRUGO,
+                        emif->debugfs_root, emif, &emif_mr4_fops);
+        if (IS_ERR(dentry)) {
+                ret = PTR_ERR(dentry);
+                goto err1;
+        }
+
+        return 0;
+err1:
+        debugfs_remove_recursive(emif->debugfs_root);
+err0:
+        return ret;
+}
+
+static void __exit emif_debugfs_exit(struct emif_data *emif)
+{
+        debugfs_remove_recursive(emif->debugfs_root);
+        emif->debugfs_root = NULL;
+}
+
 /*
  * Calculate the period of DDR clock from frequency value
  */
@@ -1175,6 +1302,7 @@ static int __init_or_module emif_probe(struct platform_device *pdev)
         }
 
         emif_onetime_settings(emif);
+        emif_debugfs_init(emif);
         disable_and_clear_all_interrupts(emif);
         setup_interrupts(emif, irq);
 
@@ -1198,6 +1326,15 @@ error:
         return -ENODEV;
 }
 
+static int __exit emif_remove(struct platform_device *pdev)
+{
+        struct emif_data *emif = platform_get_drvdata(pdev);
+
+        emif_debugfs_exit(emif);
+
+        return 0;
+}
+
 static void emif_shutdown(struct platform_device *pdev)
 {
         struct emif_data        *emif = platform_get_drvdata(pdev);
@@ -1508,6 +1645,7 @@ static void __attribute__((unused)) freq_post_notify_handling(void)
 }
 
 static struct platform_driver emif_driver = {
+        .remove         = __exit_p(emif_remove),
         .shutdown       = emif_shutdown,
         .driver = {
                 .name = "emif",