1 files changed, 48 insertions, 59 deletions

diff --git a/arch/powerpc/platforms/86xx/mpc8610_hpcd.c b/arch/powerpc/platforms/86xx/mpc8610_hpcd.c
index a896511690c2..74e018ef724b 100644
--- a/arch/powerpc/platforms/86xx/mpc8610_hpcd.c
+++ b/arch/powerpc/platforms/86xx/mpc8610_hpcd.c
@@ -39,12 +39,19 @@
 #include <sysdev/fsl_pci.h>
 #include <sysdev/fsl_soc.h>
 #include <sysdev/simple_gpio.h>
+#include <asm/fsl_guts.h>
 
 #include "mpc86xx.h"
 
 static struct device_node *pixis_node;
 static unsigned char *pixis_bdcfg0, *pixis_arch;
 
+/* DIU Pixel Clock bits of the CLKDVDR Global Utilities register */
+#define CLKDVDR_PXCKEN		0x80000000
+#define CLKDVDR_PXCKINV		0x10000000
+#define CLKDVDR_PXCKDLY		0x06000000
+#define CLKDVDR_PXCLK_MASK	0x001F0000
+
 #ifdef CONFIG_SUSPEND
 static irqreturn_t mpc8610_sw9_irq(int irq, void *data)
 {
@@ -205,72 +212,54 @@ void mpc8610hpcd_set_monitor_port(int monitor_port)
 			     bdcfg[monitor_port]);
 }
 
+/**
+ * mpc8610hpcd_set_pixel_clock: program the DIU's clock
+ *
+ * @pixclock: the wavelength, in picoseconds, of the clock
+ */
 void mpc8610hpcd_set_pixel_clock(unsigned int pixclock)
 {
-	u32 __iomem *clkdvdr;
-	u32 temp;
-	/* variables for pixel clock calcs */
-	ulong  bestval, bestfreq, speed_ccb, minpixclock, maxpixclock;
-	ulong pixval;
-	long err;
-	int i;
-
-	clkdvdr = ioremap(get_immrbase() + 0xe0800, sizeof(u32));
-	if (!clkdvdr) {
-		printk(KERN_ERR "Err: can't map clock divider register!\n");
+	struct device_node *guts_np = NULL;
+	struct ccsr_guts_86xx __iomem *guts;
+	unsigned long freq;
+	u64 temp;
+	u32 pxclk;
+
+	/* Map the global utilities registers. */
+	guts_np = of_find_compatible_node(NULL, NULL, "fsl,mpc8610-guts");
+	if (!guts_np) {
+		pr_err("mpc8610hpcd: missing global utilties device node\n");
 		return;
 	}
 
-	/* Pixel Clock configuration */
-	speed_ccb = fsl_get_sys_freq();
-
-	/* Calculate the pixel clock with the smallest error */
-	/* calculate the following in steps to avoid overflow */
-	pr_debug("DIU pixclock in ps - %d\n", pixclock);
-	temp = 1000000000/pixclock;
-	temp *= 1000;
-	pixclock = temp;
-	pr_debug("DIU pixclock freq - %u\n", pixclock);
-
-	temp = pixclock * 5 / 100;
-	pr_debug("deviation = %d\n", temp);
-	minpixclock = pixclock - temp;
-	maxpixclock = pixclock + temp;
-	pr_debug("DIU minpixclock - %lu\n", minpixclock);
-	pr_debug("DIU maxpixclock - %lu\n", maxpixclock);
-	pixval = speed_ccb/pixclock;
-	pr_debug("DIU pixval = %lu\n", pixval);
-
-	err = 100000000;
-	bestval = pixval;
-	pr_debug("DIU bestval = %lu\n", bestval);
-
-	bestfreq = 0;
-	for (i = -1; i <= 1; i++) {
-		temp = speed_ccb / ((pixval+i) + 1);
-		pr_debug("DIU test pixval i= %d, pixval=%lu, temp freq. = %u\n",
-							i, pixval, temp);
-		if ((temp < minpixclock) || (temp > maxpixclock))
-			pr_debug("DIU exceeds monitor range (%lu to %lu)\n",
-				minpixclock, maxpixclock);
-		else if (abs(temp - pixclock) < err) {
-		  pr_debug("Entered the else if block %d\n", i);
-			err = abs(temp - pixclock);
-			bestval = pixval+i;
-			bestfreq = temp;
-		}
+	guts = of_iomap(guts_np, 0);
+	of_node_put(guts_np);
+	if (!guts) {
+		pr_err("mpc8610hpcd: could not map global utilties device\n");
+		return;
 	}
 
-	pr_debug("DIU chose = %lx\n", bestval);
-	pr_debug("DIU error = %ld\n NomPixClk ", err);
-	pr_debug("DIU: Best Freq = %lx\n", bestfreq);
-	/* Modify PXCLK in GUTS CLKDVDR */
-	pr_debug("DIU: Current value of CLKDVDR = 0x%08x\n", (*clkdvdr));
-	temp = (*clkdvdr) & 0x2000FFFF;
-	*clkdvdr = temp;		/* turn off clock */
-	*clkdvdr = temp | 0x80000000 | (((bestval) & 0x1F) << 16);
-	pr_debug("DIU: Modified value of CLKDVDR = 0x%08x\n", (*clkdvdr));
-	iounmap(clkdvdr);
+	/* Convert pixclock from a wavelength to a frequency */
+	temp = 1000000000000ULL;
+	do_div(temp, pixclock);
+	freq = temp;
+
+	/*
+	 * 'pxclk' is the ratio of the platform clock to the pixel clock.
+	 * On the MPC8610, the value programmed into CLKDVDR is the ratio
+	 * minus one.  The valid range of values is 2-31.
+	 */
+	pxclk = DIV_ROUND_CLOSEST(fsl_get_sys_freq(), freq) - 1;
+	pxclk = clamp_t(u32, pxclk, 2, 31);
+
+	/* Disable the pixel clock, and set it to non-inverted and no delay */
+	clrbits32(&guts->clkdvdr,
+		  CLKDVDR_PXCKEN | CLKDVDR_PXCKDLY | CLKDVDR_PXCLK_MASK);
+
+	/* Enable the clock and set the pxclk */
+	setbits32(&guts->clkdvdr, CLKDVDR_PXCKEN | (pxclk << 16));
+
+	iounmap(guts);
 }
 
 ssize_t mpc8610hpcd_show_monitor_port(int monitor_port, char *buf)