ARM: S3C: CPUFREQ: Add debugfs support for cpufreq

Add debugfs support for the cpufreq driver to allow
information about the system state to be exported to
the user.

Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

10 files changed, 317 insertions, 0 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index c7a83efef0b9..f07a4ba281bc 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1329,6 +1329,12 @@ config CPU_FREQ_S3C24XX_IODEBUG
         help
           Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
 
+config CPU_FREQ_S3C24XX_DEBUGFS
+        bool "Export debugfs for CPUFreq"
+        depends on CPU_FREQ_S3C24XX && DEBUG_FS
+        help
+          Export status information via debugfs.
+
 endif
 
 source "drivers/cpuidle/Kconfig"
diff --git a/arch/arm/mach-s3c2410/cpu-freq.c b/arch/arm/mach-s3c2410/cpu-freq.c
index f2cbdbab0df6..9d1186877d08 100644
--- a/arch/arm/mach-s3c2410/cpu-freq.c
+++ b/arch/arm/mach-s3c2410/cpu-freq.c
@@ -111,6 +111,8 @@ static struct s3c_cpufreq_info s3c2410_cpufreq_info = {
         .set_refresh    = s3c2410_cpufreq_setrefresh,
         .set_divs       = s3c2410_cpufreq_setdivs,
         .calc_divs      = s3c2410_cpufreq_calcdivs,
+
+        .debug_io_show  = s3c_cpufreq_debugfs_call(s3c2410_iotiming_debugfs),
 };
 
 static int s3c2410_cpufreq_add(struct sys_device *sysdev)
diff --git a/arch/arm/mach-s3c2412/cpu-freq.c b/arch/arm/mach-s3c2412/cpu-freq.c
index 21a66178d9b7..eb3ea1721335 100644
--- a/arch/arm/mach-s3c2412/cpu-freq.c
+++ b/arch/arm/mach-s3c2412/cpu-freq.c
@@ -190,6 +190,8 @@ static struct s3c_cpufreq_info s3c2412_cpufreq_info = {
         .get_iotiming   = s3c2412_iotiming_get,
 
         .resume_clocks  = s3c2412_setup_clocks,
+
+        .debug_io_show  = s3c_cpufreq_debugfs_call(s3c2412_iotiming_debugfs),
 };
 
 static int s3c2412_cpufreq_add(struct sys_device *sysdev)
diff --git a/arch/arm/plat-s3c24xx/Makefile b/arch/arm/plat-s3c24xx/Makefile
index 8759c070fd9a..f34937515804 100644
--- a/arch/arm/plat-s3c24xx/Makefile
+++ b/arch/arm/plat-s3c24xx/Makefile
@@ -21,6 +21,7 @@ obj-y				+= clock.o
 obj-$(CONFIG_S3C24XX_DCLK)      += clock-dclk.o
 
 obj-$(CONFIG_CPU_FREQ_S3C24XX)  += cpu-freq.o
+obj-$(CONFIG_CPU_FREQ_S3C24XX_DEBUGFS) += cpu-freq-debugfs.o
 
 # Architecture dependant builds
 
diff --git a/arch/arm/plat-s3c24xx/cpu-freq-debugfs.c b/arch/arm/plat-s3c24xx/cpu-freq-debugfs.c
new file mode 100644
index 000000000000..a9276667c2fb
--- /dev/null
+++ b/arch/arm/plat-s3c24xx/cpu-freq-debugfs.c
@@ -0,0 +1,199 @@
+/* linux/arch/arm/plat-s3c24xx/cpu-freq-debugfs.c
+ *
+ * Copyright (c) 2009 Simtec Electronics
+ *      http://armlinux.simtec.co.uk/
+ *      Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C24XX CPU Frequency scaling - debugfs status support
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/cpufreq.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/err.h>
+
+#include <plat/cpu-freq-core.h>
+
+static struct dentry *dbgfs_root;
+static struct dentry *dbgfs_file_io;
+static struct dentry *dbgfs_file_info;
+static struct dentry *dbgfs_file_board;
+
+#define print_ns(x) ((x) / 10), ((x) % 10)
+
+static void show_max(struct seq_file *seq, struct s3c_freq *f)
+{
+        seq_printf(seq, "MAX: F=%lu, H=%lu, P=%lu, A=%lu\n",
+                   f->fclk, f->hclk, f->pclk, f->armclk);
+}
+
+static int board_show(struct seq_file *seq, void *p)
+{
+        struct s3c_cpufreq_config *cfg;
+        struct s3c_cpufreq_board *brd;
+
+        cfg = s3c_cpufreq_getconfig();
+        if (!cfg) {
+                seq_printf(seq, "no configuration registered\n");
+                return 0;
+        }
+
+        brd = cfg->board;
+        if (!brd) {
+                seq_printf(seq, "no board definition set?\n");
+                return 0;
+        }
+
+        seq_printf(seq, "SDRAM refresh %u ns\n", brd->refresh);
+        seq_printf(seq, "auto_io=%u\n", brd->auto_io);
+        seq_printf(seq, "need_io=%u\n", brd->need_io);
+
+        show_max(seq, &brd->max);
+
+
+        return 0;
+}
+
+static int fops_board_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, board_show, NULL);
+}
+
+static const struct file_operations fops_board = {
+        .open           = fops_board_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+        .owner          = THIS_MODULE,
+};
+
+static int info_show(struct seq_file *seq, void *p)
+{
+        struct s3c_cpufreq_config *cfg;
+
+        cfg = s3c_cpufreq_getconfig();
+        if (!cfg) {
+                seq_printf(seq, "no configuration registered\n");
+                return 0;
+        }
+
+        seq_printf(seq, "  FCLK %ld Hz\n", cfg->freq.fclk);
+        seq_printf(seq, "  HCLK %ld Hz (%lu.%lu ns)\n",
+                   cfg->freq.hclk, print_ns(cfg->freq.hclk_tns));
+        seq_printf(seq, "  PCLK %ld Hz\n", cfg->freq.hclk);
+        seq_printf(seq, "ARMCLK %ld Hz\n", cfg->freq.armclk);
+        seq_printf(seq, "\n");
+
+        show_max(seq, &cfg->max);
+
+        seq_printf(seq, "Divisors: P=%d, H=%d, A=%d, dvs=%s\n",
+                   cfg->divs.h_divisor, cfg->divs.p_divisor,
+                   cfg->divs.arm_divisor, cfg->divs.dvs ? "on" : "off");
+        seq_printf(seq, "\n");
+
+        seq_printf(seq, "lock_pll=%u\n", cfg->lock_pll);
+
+        return 0;
+}
+
+static int fops_info_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, info_show, NULL);
+}
+
+static const struct file_operations fops_info = {
+        .open           = fops_info_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+        .owner          = THIS_MODULE,
+};
+
+static int io_show(struct seq_file *seq, void *p)
+{
+        void (*show_bank)(struct seq_file *, struct s3c_cpufreq_config *, union s3c_iobank *);
+        struct s3c_cpufreq_config *cfg;
+        struct s3c_iotimings *iot;
+        union s3c_iobank *iob;
+        int bank;
+
+        cfg = s3c_cpufreq_getconfig();
+        if (!cfg) {
+                seq_printf(seq, "no configuration registered\n");
+                return 0;
+        }
+
+        show_bank = cfg->info->debug_io_show;
+        if (!show_bank) {
+                seq_printf(seq, "no code to show bank timing\n");
+                return 0;
+        }
+
+        iot = s3c_cpufreq_getiotimings();
+        if (!iot) {
+                seq_printf(seq, "no io timings registered\n");
+                return 0;
+        }
+
+        seq_printf(seq, "hclk period is %lu.%lu ns\n", print_ns(cfg->freq.hclk_tns));
+
+        for (bank = 0; bank < MAX_BANKS; bank++) {
+                iob = &iot->bank[bank];
+
+                seq_printf(seq, "bank %d: ", bank);
+
+                if (!iob->io_2410) {
+                        seq_printf(seq, "nothing set\n");
+                        continue;
+                }
+
+                show_bank(seq, cfg, iob);
+        }
+
+        return 0;
+}
+
+static int fops_io_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, io_show, NULL);
+}
+
+static const struct file_operations fops_io = {
+        .open           = fops_io_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+        .owner          = THIS_MODULE,
+};
+
+
+static int __init s3c_freq_debugfs_init(void)
+{
+        dbgfs_root = debugfs_create_dir("s3c-cpufreq", NULL);
+        if (IS_ERR(dbgfs_root)) {
+                printk(KERN_ERR "%s: error creating debugfs root\n", __func__);
+                return PTR_ERR(dbgfs_root);
+        }
+
+        dbgfs_file_io = debugfs_create_file("io-timing", S_IRUGO, dbgfs_root,
+                                            NULL, &fops_io);
+
+        dbgfs_file_info = debugfs_create_file("info", S_IRUGO, dbgfs_root,
+                                              NULL, &fops_info);
+
+        dbgfs_file_board = debugfs_create_file("board", S_IRUGO, dbgfs_root,
+                                               NULL, &fops_board);
+
+        return 0;
+}
+
+late_initcall(s3c_freq_debugfs_init);
+
diff --git a/arch/arm/plat-s3c24xx/cpu-freq.c b/arch/arm/plat-s3c24xx/cpu-freq.c
index 40ff7e2569dc..4f1b789a1173 100644
--- a/arch/arm/plat-s3c24xx/cpu-freq.c
+++ b/arch/arm/plat-s3c24xx/cpu-freq.c
@@ -50,6 +50,18 @@ static struct clk *clk_hclk;
 static struct clk *clk_pclk;
 static struct clk *clk_arm;
 
+#ifdef CONFIG_CPU_FREQ_S3C24XX_DEBUGFS
+struct s3c_cpufreq_config *s3c_cpufreq_getconfig(void)
+{
+        return &cpu_cur;
+}
+
+struct s3c_iotimings *s3c_cpufreq_getiotimings(void)
+{
+        return &s3c24xx_iotiming;
+}
+#endif /* CONFIG_CPU_FREQ_S3C24XX_DEBUGFS */
+
 static void s3c_cpufreq_getcur(struct s3c_cpufreq_config *cfg)
 {
         unsigned long fclk, pclk, hclk, armclk;
diff --git a/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h b/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h
index f02b3c06c1e0..efeb025affc7 100644
--- a/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h
+++ b/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h
@@ -13,6 +13,8 @@
 
 #include <plat/cpu-freq.h>
 
+struct seq_file;
+
 #define MAX_BANKS (8)
 #define S3C2412_MAX_IO  (8)
 
@@ -181,6 +183,10 @@ struct s3c_cpufreq_info {
                                           struct cpufreq_frequency_table *t,
                                           size_t table_size);
 
+        void            (*debug_io_show)(struct seq_file *seq,
+                                         struct s3c_cpufreq_config *cfg,
+                                         union s3c_iobank *iob);
+
         void            (*set_refresh)(struct s3c_cpufreq_config *cfg);
         void            (*set_fvco)(struct s3c_cpufreq_config *cfg);
         void            (*set_divs)(struct s3c_cpufreq_config *cfg);
@@ -191,6 +197,24 @@ extern int s3c_cpufreq_register(struct s3c_cpufreq_info *info);
 
 extern int s3c_plltab_register(struct cpufreq_frequency_table *plls, unsigned int plls_no);
 
+/* exports and utilities for debugfs */
+extern struct s3c_cpufreq_config *s3c_cpufreq_getconfig(void);
+extern struct s3c_iotimings *s3c_cpufreq_getiotimings(void);
+
+extern void s3c2410_iotiming_debugfs(struct seq_file *seq,
+                                     struct s3c_cpufreq_config *cfg,
+                                     union s3c_iobank *iob);
+
+extern void s3c2412_iotiming_debugfs(struct seq_file *seq,
+                                     struct s3c_cpufreq_config *cfg,
+                                     union s3c_iobank *iob);
+
+#ifdef CONFIG_CPU_FREQ_S3C24XX_DEBUGFS
+#define s3c_cpufreq_debugfs_call(x) x
+#else
+#define s3c_cpufreq_debugfs_call(x) NULL
+#endif
+
 /* Useful utility functions. */
 
 extern struct clk *s3c_cpufreq_clk_get(struct device *, const char *);
diff --git a/arch/arm/plat-s3c24xx/s3c2410-iotiming.c b/arch/arm/plat-s3c24xx/s3c2410-iotiming.c
index 26fe2129cf25..d0a3a145cd4d 100644
--- a/arch/arm/plat-s3c24xx/s3c2410-iotiming.c
+++ b/arch/arm/plat-s3c24xx/s3c2410-iotiming.c
@@ -15,6 +15,7 @@
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/cpufreq.h>
+#include <linux/seq_file.h>
 #include <linux/io.h>
 
 #include <mach/map.h>
@@ -304,6 +305,50 @@ void s3c2410_iotiming_getbank(struct s3c_cpufreq_config *cfg,
 }
 
 /**
+ * s3c2410_iotiming_debugfs - debugfs show io bank timing information
+ * @seq: The seq_file to write output to using seq_printf().
+ * @cfg: The current configuration.
+ * @iob: The IO bank information to decode.
+ */
+void s3c2410_iotiming_debugfs(struct seq_file *seq,
+                              struct s3c_cpufreq_config *cfg,
+                              union s3c_iobank *iob)
+{
+        struct s3c2410_iobank_timing *bt = iob->io_2410;
+        unsigned long bankcon = bt->bankcon;
+        unsigned long hclk = cfg->freq.hclk_tns;
+        unsigned int tacs;
+        unsigned int tcos;
+        unsigned int tacc;
+        unsigned int tcoh;
+        unsigned int tcah;
+
+        seq_printf(seq, "BANKCON=0x%08lx\n", bankcon);
+
+        tcah = get_0124(hclk, bankcon >> S3C2410_BANKCON_Tcah_SHIFT);
+        tcoh = get_0124(hclk, bankcon >> S3C2410_BANKCON_Tcoh_SHIFT);
+        tcos = get_0124(hclk, bankcon >> S3C2410_BANKCON_Tcos_SHIFT);
+        tacs = get_0124(hclk, bankcon >> S3C2410_BANKCON_Tacs_SHIFT);
+        tacc = get_tacc(hclk, bankcon >> S3C2410_BANKCON_Tacc_SHIFT);
+
+        seq_printf(seq,
+                   "\tRead: Tacs=%d.%d, Tcos=%d.%d, Tacc=%d.%d, Tcoh=%d.%d, Tcah=%d.%d\n",
+                   print_ns(bt->tacs),
+                   print_ns(bt->tcos),
+                   print_ns(bt->tacc),
+                   print_ns(bt->tcoh),
+                   print_ns(bt->tcah));
+
+        seq_printf(seq,
+                   "\t Set: Tacs=%d.%d, Tcos=%d.%d, Tacc=%d.%d, Tcoh=%d.%d, Tcah=%d.%d\n",
+                   print_ns(tacs),
+                   print_ns(tcos),
+                   print_ns(tacc),
+                   print_ns(tcoh),
+                   print_ns(tcah));
+}
+
+/**
  * s3c2410_iotiming_calc - Calculate bank timing for frequency change.
  * @cfg: The frequency configuration
  * @iot: The IO timing information to fill out.
diff --git a/arch/arm/plat-s3c24xx/s3c2412-iotiming.c b/arch/arm/plat-s3c24xx/s3c2412-iotiming.c
index a3648cba0eb9..fd45e47facbc 100644
--- a/arch/arm/plat-s3c24xx/s3c2412-iotiming.c
+++ b/arch/arm/plat-s3c24xx/s3c2412-iotiming.c
@@ -16,6 +16,7 @@
 #include <linux/interrupt.h>
 #include <linux/ioport.h>
 #include <linux/cpufreq.h>
+#include <linux/seq_file.h>
 #include <linux/sysdev.h>
 #include <linux/delay.h>
 #include <linux/clk.h>
@@ -109,6 +110,29 @@ static int s3c2412_calc_bank(struct s3c_cpufreq_config *cfg,
 }
 
 /**
+ * s3c2412_iotiming_debugfs - debugfs show io bank timing information
+ * @seq: The seq_file to write output to using seq_printf().
+ * @cfg: The current configuration.
+ * @iob: The IO bank information to decode.
+*/
+void s3c2412_iotiming_debugfs(struct seq_file *seq,
+                              struct s3c_cpufreq_config *cfg,
+                              union s3c_iobank *iob)
+{
+        struct s3c2412_iobank_timing *bt = iob->io_2412;
+
+        seq_printf(seq,
+                   "\tRead: idcy=%d.%d wstrd=%d.%d wstwr=%d,%d"
+                   "wstoen=%d.%d wstwen=%d.%d wstbrd=%d.%d\n",
+                   print_ns(bt->idcy),
+                   print_ns(bt->wstrd),
+                   print_ns(bt->wstwr),
+                   print_ns(bt->wstoen),
+                   print_ns(bt->wstwen),
+                   print_ns(bt->wstbrd));
+}
+
+/**
  * s3c2412_iotiming_calc - calculate all the bank divisor settings.
  * @cfg: The current frequency configuration.
  * @iot: The bank timing information.
diff --git a/arch/arm/plat-s3c24xx/s3c2440-cpufreq.c b/arch/arm/plat-s3c24xx/s3c2440-cpufreq.c
index c177a20319e2..ae2e6c604f27 100644
--- a/arch/arm/plat-s3c24xx/s3c2440-cpufreq.c
+++ b/arch/arm/plat-s3c24xx/s3c2440-cpufreq.c
@@ -266,6 +266,8 @@ struct s3c_cpufreq_info s3c2440_cpufreq_info = {
         .calc_freqtable = s3c2440_cpufreq_calctable,
 
         .resume_clocks  = s3c244x_setup_clocks,
+
+        .debug_io_show  = s3c_cpufreq_debugfs_call(s3c2410_iotiming_debugfs),
 };
 
 static int s3c2440_cpufreq_add(struct sys_device *sysdev)