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>

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"

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)

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)

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
 

arch/arm/plat-s3c24xx/cpu-freq-debugfs.c

+/* 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);
+

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;

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 *);

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>
@@ -303,6 +304,50 @@ void s3c2410_iotiming_getbank(struct s3c_cpufreq_config *cfg,
 	bt->tacc = get_tacc(hclk, bankcon >> S3C2410_BANKCON_Tacc_SHIFT);
 }
 
+/**
+ * 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

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>
@@ -108,6 +109,29 @@ static int s3c2412_calc_bank(struct s3c_cpufreq_config *cfg,
 	return err;
 }
 
+/**
+ * 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.

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)