在 2017-09-28 18:27，Maxime Ripard 写道：
Hi,
On Sat, Sep 23, 2017 at 12:15:29AM +0000, Icenowy Zheng wrote:
The A64 PLL_CPU clock has the same instability if some factor changed
without the PLL gated like other SoCs with sun6i-style CCU, e.g. A33,
H3.
Add the mux and pll notifiers for A64 CPU clock to workaround the
problem.
Fixes: c6a0637460c2 ("clk: sunxi-ng: Add A64 clocks")
Signed-off-by: Icenowy Zheng <icenowy@xxxxxxx>
---
drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 28
+++++++++++++++++++++++++++-
1 file changed, 27 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
index 2bb4cabf802f..b55fa69dd0c1 100644
--- a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
+++ b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
@@ -879,11 +879,26 @@ static const struct sunxi_ccu_desc
sun50i_a64_ccu_desc = {
.num_resets = ARRAY_SIZE(sun50i_a64_ccu_resets),
};
+static struct ccu_pll_nb sun50i_a64_pll_cpu_nb = {
+ .common = &pll_cpux_clk.common,
+ /* copy from pll_cpux_clk */
+ .enable = BIT(31),
+ .lock = BIT(28),
+};
+
+static struct ccu_mux_nb sun50i_a64_cpu_nb = {
+ .common = &cpux_clk.common,
+ .cm = &cpux_clk.mux,
+ .delay_us = 1, /* > 8 clock cycles at 24 MHz */
+ .bypass_index = 1, /* index of 24 MHz oscillator */
+};
+
static int sun50i_a64_ccu_probe(struct platform_device *pdev)
{
struct resource *res;
void __iomem *reg;
u32 val;
+ int ret;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
reg = devm_ioremap_resource(&pdev->dev, res);
@@ -897,7 +912,18 @@ static int sun50i_a64_ccu_probe(struct
platform_device *pdev)
writel(0x515, reg + SUN50I_A64_PLL_MIPI_REG);
- return sunxi_ccu_probe(pdev->dev.of_node, reg,
&sun50i_a64_ccu_desc);
+ ret = sunxi_ccu_probe(pdev->dev.of_node, reg, &sun50i_a64_ccu_desc);
+ if (ret)
+ return ret;
+
+ /* Gate then ungate PLL CPU after any rate changes */
+ ccu_pll_notifier_register(&sun50i_a64_pll_cpu_nb);
+
+ /* Reparent CPU during PLL CPU rate changes */
+ ccu_mux_notifier_register(pll_cpux_clk.common.hw.clk,
+ &sun50i_a64_cpu_nb);
+
+ return 0;
So this is the fourth user of the exact same code, can you turn that
into a shared function?
I think it's not so worthful to extract the code, as:
- the notifier structs contains info of the clocks
- A31 seems not to need the PLL notifier.
Thanks!
Maxime
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