diff options
| author |   Geert Uytterhoeven <geert+renesas@glider.be> | 2021-03-26 13:01:00 +0100 |
|---|---|---|
| committer | Geert Uytterhoeven <geert+renesas@glider.be> | 2021-05-11 09:57:06 +0200 |
| commit | 3a0e84845891eebccce767b4f8cd5ed1b9bffc14 (patch) | |
| tree | 7d4a2b2c9b1fb524e8ef634b98df8a935a34cb73 /drivers/clk/renesas/rcar-gen3-cpg.c | |
| parent | clk: renesas: rcar-gen3: Add custom clock for PLLs (diff) | |
| download | linux-dev-3a0e84845891eebccce767b4f8cd5ed1b9bffc14.tar.xz linux-dev-3a0e84845891eebccce767b4f8cd5ed1b9bffc14.zip | |
clk: renesas: rcar-gen3: Add boost support to Z clocks
Add support for switching the Z and Z2 clocks between normal and boost
modes, by requesting clock rate changes to parent PLLs.
Inspired by a patch in the BSP by Takeshi Kihara
<takeshi.kihara.df@renesas.com>.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20210326120100.1577596-8-geert+renesas@glider.be
Diffstat (limited to 'drivers/clk/renesas/rcar-gen3-cpg.c')
| -rw-r--r-- | drivers/clk/renesas/rcar-gen3-cpg.c | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/drivers/clk/renesas/rcar-gen3-cpg.c b/drivers/clk/renesas/rcar-gen3-cpg.c index cc9a116d7d09..558191c99b48 100644 --- a/drivers/clk/renesas/rcar-gen3-cpg.c +++ b/drivers/clk/renesas/rcar-gen3-cpg.c @@ -165,6 +165,7 @@ struct cpg_z_clk { struct clk_hw hw; void __iomem *reg; void __iomem *kick_reg; + unsigned long max_rate; /* Maximum rate for normal mode */ unsigned int fixed_div; u32 mask; }; @@ -190,7 +191,18 @@ static int cpg_z_clk_determine_rate(struct clk_hw *hw, { struct cpg_z_clk *zclk = to_z_clk(hw); unsigned int min_mult, max_mult, mult; - unsigned long prate; + unsigned long rate, prate; + + rate = min(req->rate, req->max_rate); + if (rate <= zclk->max_rate) { + /* Set parent rate to initial value for normal modes */ + prate = zclk->max_rate; + } else { + /* Set increased parent rate for boost modes */ + prate = rate; + } + req->best_parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw), + prate * zclk->fixed_div); prate = req->best_parent_rate / zclk->fixed_div; min_mult = max(div64_ul(req->min_rate * 32ULL, prate), 1ULL); @@ -198,7 +210,7 @@ static int cpg_z_clk_determine_rate(struct clk_hw *hw, if (max_mult < min_mult) return -EINVAL; - mult = DIV_ROUND_CLOSEST_ULL(req->rate * 32ULL, prate); + mult = DIV_ROUND_CLOSEST_ULL(rate * 32ULL, prate); mult = clamp(mult, min_mult, max_mult); req->rate = DIV_ROUND_CLOSEST_ULL((u64)prate * mult, 32); @@ -268,7 +280,7 @@ static struct clk * __init cpg_z_clk_register(const char *name, init.name = name; init.ops = &cpg_z_clk_ops; - init.flags = 0; + init.flags = CLK_SET_RATE_PARENT; init.parent_names = &parent_name; init.num_parents = 1; @@ -279,9 +291,13 @@ static struct clk * __init cpg_z_clk_register(const char *name, zclk->fixed_div = div; /* PLLVCO x 1/div x SYS-CPU divider */ clk = clk_register(NULL, &zclk->hw); - if (IS_ERR(clk)) + if (IS_ERR(clk)) { kfree(zclk); + return clk; + } + zclk->max_rate = clk_hw_get_rate(clk_hw_get_parent(&zclk->hw)) / + zclk->fixed_div; return clk; } |