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Diffstat (limited to 'arch/arm/mach-omap2/clock34xx.c')
-rw-r--r--arch/arm/mach-omap2/clock34xx.c42
1 files changed, 31 insertions, 11 deletions
diff --git a/arch/arm/mach-omap2/clock34xx.c b/arch/arm/mach-omap2/clock34xx.c
index 9e43fe5209d3..045da923e75b 100644
--- a/arch/arm/mach-omap2/clock34xx.c
+++ b/arch/arm/mach-omap2/clock34xx.c
@@ -286,6 +286,20 @@ static struct omap_clk omap34xx_clks[] = {
#define MIN_SDRC_DLL_LOCK_FREQ 83000000
+#define CYCLES_PER_MHZ 1000000
+
+/* Scale factor for fixed-point arith in omap3_core_dpll_m2_set_rate() */
+#define SDRC_MPURATE_SCALE 8
+
+/* 2^SDRC_MPURATE_BASE_SHIFT: MPU MHz that SDRC_MPURATE_LOOPS is defined for */
+#define SDRC_MPURATE_BASE_SHIFT 9
+
+/*
+ * SDRC_MPURATE_LOOPS: Number of MPU loops to execute at
+ * 2^MPURATE_BASE_SHIFT MHz for SDRC to stabilize
+ */
+#define SDRC_MPURATE_LOOPS 96
+
/**
* omap3_dpll_recalc - recalculate DPLL rate
* @clk: DPLL struct clk
@@ -709,7 +723,8 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate)
{
u32 new_div = 0;
u32 unlock_dll = 0;
- unsigned long validrate, sdrcrate;
+ u32 c;
+ unsigned long validrate, sdrcrate, mpurate;
struct omap_sdrc_params *sp;
if (!clk || !rate)
@@ -718,18 +733,15 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate)
if (clk != &dpll3_m2_ck)
return -EINVAL;
- if (rate == clk->rate)
- return 0;
-
validrate = omap2_clksel_round_rate_div(clk, rate, &new_div);
if (validrate != rate)
return -EINVAL;
sdrcrate = sdrc_ick.rate;
if (rate > clk->rate)
- sdrcrate <<= ((rate / clk->rate) - 1);
+ sdrcrate <<= ((rate / clk->rate) >> 1);
else
- sdrcrate >>= ((clk->rate / rate) - 1);
+ sdrcrate >>= ((clk->rate / rate) >> 1);
sp = omap2_sdrc_get_params(sdrcrate);
if (!sp)
@@ -740,17 +752,25 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate)
unlock_dll = 1;
}
+ /*
+ * XXX This only needs to be done when the CPU frequency changes
+ */
+ mpurate = arm_fck.rate / CYCLES_PER_MHZ;
+ c = (mpurate << SDRC_MPURATE_SCALE) >> SDRC_MPURATE_BASE_SHIFT;
+ c += 1; /* for safety */
+ c *= SDRC_MPURATE_LOOPS;
+ c >>= SDRC_MPURATE_SCALE;
+ if (c == 0)
+ c = 1;
+
pr_debug("clock: changing CORE DPLL rate from %lu to %lu\n", clk->rate,
validrate);
pr_debug("clock: SDRC timing params used: %08x %08x %08x\n",
sp->rfr_ctrl, sp->actim_ctrla, sp->actim_ctrlb);
- /* REVISIT: SRAM code doesn't support other M2 divisors yet */
- WARN_ON(new_div != 1 && new_div != 2);
-
- /* REVISIT: Add SDRC_MR changing to this code also */
omap3_configure_core_dpll(sp->rfr_ctrl, sp->actim_ctrla,
- sp->actim_ctrlb, new_div, unlock_dll);
+ sp->actim_ctrlb, new_div, unlock_dll, c,
+ sp->mr, rate > clk->rate);
return 0;
}