]> git.sur5r.net Git - u-boot/commitdiff
ARM: uniphier: compute SSCPLL values more precisely
authorMasahiro Yamada <yamada.masahiro@socionext.com>
Wed, 6 Dec 2017 05:16:33 +0000 (14:16 +0900)
committerMasahiro Yamada <yamada.masahiro@socionext.com>
Mon, 11 Dec 2017 15:36:11 +0000 (00:36 +0900)
Use DIV_ROUND_CLOSEST().  To make the JK value even more precise,
I used a bigger coefficient, then divide it by 512.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
arch/arm/mach-uniphier/clk/pll-base-ld20.c

index 45fdf0a3226c376066b64d5cfb803f00f733305f..c9b78b9e8811f7379701b3286e67d8611061eba2 100644 (file)
@@ -7,6 +7,7 @@
 
 #include <linux/bitops.h>
 #include <linux/delay.h>
+#include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/io.h>
 #include <linux/sizes.h>
@@ -41,13 +42,14 @@ int uniphier_ld20_sscpll_init(unsigned long reg_base, unsigned int freq,
        if (freq != UNIPHIER_PLL_FREQ_DEFAULT) {
                tmp = readl(base);      /* SSCPLLCTRL */
                tmp &= ~SC_PLLCTRL_SSC_DK_MASK;
-               tmp |= (487 * freq * ssc_rate / divn / 512) &
+               tmp |= DIV_ROUND_CLOSEST(487UL * freq * ssc_rate, divn * 512) &
                                                        SC_PLLCTRL_SSC_DK_MASK;
                writel(tmp, base);
 
                tmp = readl(base + 4);
                tmp &= ~SC_PLLCTRL2_SSC_JK_MASK;
-               tmp |= (41859 * freq / divn) & SC_PLLCTRL2_SSC_JK_MASK;
+               tmp |= DIV_ROUND_CLOSEST(21431887UL * freq, divn * 512) &
+                                                       SC_PLLCTRL2_SSC_JK_MASK;
                writel(tmp, base + 4);
 
                udelay(50);