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Diffstat (limited to 'arch/arm/mach-tegra/tegra2_clocks.c')
-rw-r--r--arch/arm/mach-tegra/tegra2_clocks.c32
1 files changed, 26 insertions, 6 deletions
diff --git a/arch/arm/mach-tegra/tegra2_clocks.c b/arch/arm/mach-tegra/tegra2_clocks.c
index ff9e6b6..592a4ee 100644
--- a/arch/arm/mach-tegra/tegra2_clocks.c
+++ b/arch/arm/mach-tegra/tegra2_clocks.c
@@ -720,7 +720,7 @@ static void tegra2_pllx_clk_init(struct clk *c)
{
tegra2_pll_clk_init(c);
- if (tegra_sku_id() == 7)
+ if (tegra_sku_id == 7)
c->max_rate = 750000000;
}
@@ -1143,15 +1143,35 @@ static void tegra2_emc_clk_init(struct clk *c)
static long tegra2_emc_clk_round_rate(struct clk *c, unsigned long rate)
{
- long new_rate = rate;
+ long emc_rate;
+ long clk_rate;
- new_rate = tegra_emc_round_rate(new_rate);
- if (new_rate < 0)
+ /*
+ * The slowest entry in the EMC clock table that is at least as
+ * fast as rate.
+ */
+ emc_rate = tegra_emc_round_rate(rate);
+ if (emc_rate < 0)
return c->max_rate;
- BUG_ON(new_rate != tegra2_periph_clk_round_rate(c, new_rate));
+ /*
+ * The fastest rate the PLL will generate that is at most the
+ * requested rate.
+ */
+ clk_rate = tegra2_periph_clk_round_rate(c, emc_rate);
+
+ /*
+ * If this fails, and emc_rate > clk_rate, it's because the maximum
+ * rate in the EMC tables is larger than the maximum rate of the EMC
+ * clock. The EMC clock's max rate is the rate it was running when the
+ * kernel booted. Such a mismatch is probably due to using the wrong
+ * BCT, i.e. using a Tegra20 BCT with an EMC table written for Tegra25.
+ */
+ WARN_ONCE(emc_rate != clk_rate,
+ "emc_rate %ld != clk_rate %ld",
+ emc_rate, clk_rate);
- return new_rate;
+ return emc_rate;
}
static int tegra2_emc_clk_set_rate(struct clk *c, unsigned long rate)