diff options
author | Scott Wood <oss@buserror.net> | 2016-10-17 13:42:23 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-11-18 10:48:35 +0100 |
commit | dbbc5e6bcf3675db6305a0130915134d0011f37c (patch) | |
tree | 291b5a1d05e79861f5e50ea67ed469d7a6614146 /drivers/clk | |
parent | 2c5cdadeab5deac3cb5322f95077a4dfa2324326 (diff) | |
download | linux-stable-dbbc5e6bcf3675db6305a0130915134d0011f37c.tar.gz linux-stable-dbbc5e6bcf3675db6305a0130915134d0011f37c.tar.bz2 linux-stable-dbbc5e6bcf3675db6305a0130915134d0011f37c.zip |
clk: qoriq: Don't allow CPU clocks higher than starting value
commit 7c1c5413a7bdf1c9adc8d979521f1b8286366aef upstream.
The boot-time frequency of a CPU is considered its rated maximum, as we
have no other source of such information. However, this was previously
only used for chips with 80% restrictions on secondary PLLs. This
usually wasn't a problem because most chips/configs boot with a divider
of /1, with other dividers being used only for dynamic frequency
reduction. However, at least one config (LS1021A at less than 1 GHz)
uses a different divider for top speed. This was causing cpufreq to set
a frequency beyond the chip's rated speed.
This is fixed by applying a 100%-of-initial-speed limit to all CPU PLLs,
similar to the existing 80% limit that only applied to some.
Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/clk')
-rw-r--r-- | drivers/clk/clk-qoriq.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/drivers/clk/clk-qoriq.c b/drivers/clk/clk-qoriq.c index 8b77abb6bc22..a5070f9cb0d4 100644 --- a/drivers/clk/clk-qoriq.c +++ b/drivers/clk/clk-qoriq.c @@ -700,6 +700,7 @@ static struct clk * __init create_mux_common(struct clockgen *cg, struct mux_hwclock *hwc, const struct clk_ops *ops, unsigned long min_rate, + unsigned long max_rate, unsigned long pct80_rate, const char *fmt, int idx) { @@ -728,6 +729,8 @@ static struct clk * __init create_mux_common(struct clockgen *cg, continue; if (rate < min_rate) continue; + if (rate > max_rate) + continue; parent_names[j] = div->name; hwc->parent_to_clksel[j] = i; @@ -759,7 +762,7 @@ static struct clk * __init create_one_cmux(struct clockgen *cg, int idx) struct mux_hwclock *hwc; const struct clockgen_pll_div *div; unsigned long plat_rate, min_rate; - u64 pct80_rate; + u64 max_rate, pct80_rate; u32 clksel; hwc = kzalloc(sizeof(*hwc), GFP_KERNEL); @@ -787,8 +790,8 @@ static struct clk * __init create_one_cmux(struct clockgen *cg, int idx) return NULL; } - pct80_rate = clk_get_rate(div->clk); - pct80_rate *= 8; + max_rate = clk_get_rate(div->clk); + pct80_rate = max_rate * 8; do_div(pct80_rate, 10); plat_rate = clk_get_rate(cg->pll[PLATFORM_PLL].div[PLL_DIV1].clk); @@ -798,7 +801,7 @@ static struct clk * __init create_one_cmux(struct clockgen *cg, int idx) else min_rate = plat_rate / 2; - return create_mux_common(cg, hwc, &cmux_ops, min_rate, + return create_mux_common(cg, hwc, &cmux_ops, min_rate, max_rate, pct80_rate, "cg-cmux%d", idx); } @@ -813,7 +816,7 @@ static struct clk * __init create_one_hwaccel(struct clockgen *cg, int idx) hwc->reg = cg->regs + 0x20 * idx + 0x10; hwc->info = cg->info.hwaccel[idx]; - return create_mux_common(cg, hwc, &hwaccel_ops, 0, 0, + return create_mux_common(cg, hwc, &hwaccel_ops, 0, ULONG_MAX, 0, "cg-hwaccel%d", idx); } |