From 7c1c5413a7bdf1c9adc8d979521f1b8286366aef Mon Sep 17 00:00:00 2001 From: Scott Wood Date: Mon, 17 Oct 2016 13:42:23 -0500 Subject: [PATCH] clk: qoriq: Don't allow CPU clocks higher than starting value 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 Cc: stable@vger.kernel.org Signed-off-by: Stephen Boyd --- drivers/clk/clk-qoriq.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/clk/clk-qoriq.c b/drivers/clk/clk-qoriq.c index 20b105584f82..80ae2a51452d 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); } -- 2.20.1