[PATCH v2 5/5] OMAP2 clock: dynamically allocate CPUFreq frequency table

[Paul Walmsley]

Dynamically allocate the CPUFreq frequency table on OMAP2xxx chips.
This fixes some compilation problems, since the kernel may not know
what chip it is running on until boot-time.  This also reduces the size
of the CPUFreq frequency table.

Problem originally reported by Felipe Balbi <felipe.balbi at nokia.com>.
Thanks also for comments on the patch from Felipe and Kevin.

Signed-off-by: Paul Walmsley <paul at pwsan.com>
Cc: Felipe Balbi <felipe.balbi at nokia.com>
Cc: Kevin Hilman <khilman at deeprootsystems.com>
---
 arch/arm/mach-omap2/clock2xxx.c |   52 +++++++++++++++++++++++++++++++++------
 1 files changed, 44 insertions(+), 8 deletions(-)

diff --git a/arch/arm/mach-omap2/clock2xxx.c b/arch/arm/mach-omap2/clock2xxx.c
index ce6742f..5420356 100644
--- a/arch/arm/mach-omap2/clock2xxx.c
+++ b/arch/arm/mach-omap2/clock2xxx.c
@@ -449,14 +449,16 @@ int omap2_select_table_rate(struct clk *clk, unsigned long rate)
 #ifdef CONFIG_CPU_FREQ
 /*
  * Walk PRCM rate table and fillout cpufreq freq_table
+ * XXX This should be replaced by an OPP layer in the near future
  */
-static struct cpufreq_frequency_table freq_table[ARRAY_SIZE(rate_table)];
+static struct cpufreq_frequency_table *freq_table;
 
 void omap2_clk_init_cpufreq_table(struct cpufreq_frequency_table **table)
 {
-	struct prcm_config *prcm;
+	const struct prcm_config *prcm;
 	long sys_ck_rate;
 	int i = 0;
+	int tbl_sz = 0;
 
 	sys_ck_rate = clk_get_rate(sclk);
 
@@ -470,22 +472,55 @@ void omap2_clk_init_cpufreq_table(struct cpufreq_frequency_table **table)
 		if (prcm->dpll_speed == prcm->xtal_speed)
 			continue;
 
-		freq_table[i].index = i;
-		freq_table[i].frequency = prcm->mpu_speed / 1000;
-		i++;
+		tbl_sz++;
 	}
 
-	if (i == 0) {
-		printk(KERN_WARNING "%s: failed to initialize frequency "
-		       "table\n", __func__);
+	/*
+	 * XXX Ensure that we're doing what CPUFreq expects for this error
+	 * case and the following one
+	 */
+	if (tbl_sz == 0) {
+		pr_warning("%s: no matching entries in rate_table\n",
+			   __func__);
 		return;
 	}
 
+	/* Include the CPUFREQ_TABLE_END terminator entry */
+	tbl_sz++;
+
+	freq_table = kzalloc(sizeof(struct cpufreq_frequency_table) * tbl_sz,
+			     GFP_ATOMIC);
+	if (!freq_table) {
+		pr_err("%s: could not kzalloc frequency table\n", __func__);
+		return;
+	}
+
+	for (prcm = rate_table; prcm->mpu_speed; prcm++) {
+		if (!(prcm->flags & cpu_mask))
+			continue;
+		if (prcm->xtal_speed != sys_ck_rate)
+			continue;
+
+		/* don't put bypass rates in table */
+		if (prcm->dpll_speed == prcm->xtal_speed)
+			continue;
+
+		freq_table[i].index = i;
+		freq_table[i].frequency = prcm->mpu_speed / 1000;
+		i++;
+	}
+
 	freq_table[i].index = i;
 	freq_table[i].frequency = CPUFREQ_TABLE_END;
 
 	*table = &freq_table[0];
 }
+
+void omap2_clk_exit_cpufreq_table(struct cpufreq_frequency_table **table)
+{
+	kfree(freq_table);
+}
+
 #endif
 
 struct clk_functions omap2_clk_functions = {
@@ -497,6 +532,7 @@ struct clk_functions omap2_clk_functions = {
 	.clk_disable_unused	= omap2_clk_disable_unused,
 #ifdef	CONFIG_CPU_FREQ
 	.clk_init_cpufreq_table	= omap2_clk_init_cpufreq_table,
+	.clk_exit_cpufreq_table	= omap2_clk_exit_cpufreq_table,
 #endif
 };