[ARM] 4255/1: i.MX/MX1 Correct MPU PLL reference clock value.

Only System PLL clock source is selectable by CSCR_SYSTEM_SEL
bit. MPU PLL is driven by 512*CLK32 for each case.

Signed-off-by: Pavel Pisa <[e-mail]>
Signed-off-by: Russell King <[e-mail]>

arch/arm/mach-imx/cpufreq.c

···
  * imx_compute_mpctl - compute new PLL parameters
  * @new_mpctl:	pointer to location assigned by new PLL control register value
  * @cur_mpctl:	current PLL control register parameters
+ * @f_ref:	reference source frequency Hz
  * @freq:	required frequency in Hz
  * @relation:	is one of %CPUFREQ_RELATION_L (supremum)
  *		and %CPUFREQ_RELATION_H (infimum)
  */
-long imx_compute_mpctl(u32 *new_mpctl, u32 cur_mpctl, unsigned long freq, int relation)
+long imx_compute_mpctl(u32 *new_mpctl, u32 cur_mpctl, u32 f_ref, unsigned long freq, int relation)
 {
-        u32 f_ref = (CSCR & CSCR_SYSTEM_SEL) ? 16000000 : (CLK32 * 512);
         u32 mfi;
         u32 mfn;
         u32 mfd;
···
 	sysclk = imx_get_system_clk();
 
 	if (freq > sysclk / bclk_div_at_boot + 1000000) {
-		freq = imx_compute_mpctl(&mpctl0, mpctl0_at_boot, freq, relation);
+		freq = imx_compute_mpctl(&mpctl0, mpctl0_at_boot, CLK32 * 512, freq, relation);
 		if (freq < 0) {
 			printk(KERN_WARNING "imx: target frequency %ld Hz cannot be set\n", freq);
 			return -EINVAL;

arch/arm/mach-imx/generic.c

···
  *  f = 2 * f_ref * --------------------
  *                        pd + 1
  */
-static unsigned int imx_decode_pll(unsigned int pll)
+static unsigned int imx_decode_pll(unsigned int pll, u32 f_ref)
 {
 	unsigned long long ll;
 	unsigned long quot;
···
 	u32 mfn = pll & 0x3ff;
 	u32 mfd = (pll >> 16) & 0x3ff;
 	u32 pd =  (pll >> 26) & 0xf;
-	u32 f_ref = (CSCR & CSCR_SYSTEM_SEL) ? 16000000 : (CLK32 * 512);
 
 	mfi = mfi <= 5 ? 5 : mfi;
 
···
 
 unsigned int imx_get_system_clk(void)
 {
-	return imx_decode_pll(SPCTL0);
+	u32 f_ref = (CSCR & CSCR_SYSTEM_SEL) ? 16000000 : (CLK32 * 512);
+
+	return imx_decode_pll(SPCTL0, f_ref);
 }
 EXPORT_SYMBOL(imx_get_system_clk);
 
 unsigned int imx_get_mcu_clk(void)
 {
-	return imx_decode_pll(MPCTL0);
+	return imx_decode_pll(MPCTL0, CLK32 * 512);
 }
 EXPORT_SYMBOL(imx_get_mcu_clk);