[PATCH] ARM: clk: add clk-asm9260 driver

Am 15.01.2015 um 00:02 schrieb Mike Turquette:

Quoting Oleksij Rempel (2015-01-08 00:59:27)

quoted

diff --git a/drivers/clk/clk-asm9260.c b/drivers/clk/clk-asm9260.c
new file mode 100644
index 0000000..6b1c220
--- /dev/null
+++ b/drivers/clk/clk-asm9260.c

<snip>

quoted

+static const char *clk_names[] = {
+       [REFCLK]        = "oscillator",
+       [SYSPLL]        = "pll",
+       [I2S0_MCLK]     = "i2s0_mclk",
+       [I2S1_MCLK]     = "i2s1_mclk",
+       [RTC_OSC]       = "rtc_osc",
+       [USB_PLL]       = "usb_pll",
+};

Why keep this list of names? Only clk_names[REFCLK] is used below and it
is overwritten by the name supplied by DT.

Ok.

<snip>

quoted

+static void __init asm9260_acc_init(struct device_node *np)
+{
+       struct clk *clk;
+       u32 rate;
+       int n;
+       u32 accuracy = 0;
+
+       base = of_io_request_and_map(np, 0, np->name);
+       if (!base)
+               panic("%s: unable to map resource", np->name);
+
+       /* register pll */
+       rate = (ioread32(base + HW_SYSPLLCTRL) & 0xffff) * 1000000;
+
+       clk_names[REFCLK] = of_clk_get_parent_name(np, 0);
+       accuracy = clk_get_accuracy(__clk_lookup(clk_names[REFCLK]));
+       clk = clk_register_fixed_rate_with_accuracy(NULL, clk_names[SYSPLL],
+                       clk_names[REFCLK], 0, rate, accuracy);

This is different. Why do the PLLs inherit REFCLKs accuracy? Please see
__clk_recalc_accuracies in drivers/clk/clk.c if you haven't already. We
propagate accuracy through the clock tree already.

clk_register_fixed_rate overwrite accuracy to 0. If i use
clk_register_fixed_rate, then half of my clocks has accuracy = 0.

quoted

+
+       if (IS_ERR(clk))
+               panic("%s: can't register REFCLK. Check DT!", np->name);
+

<snip>

quoted

+
+       /* register clk-provider */
+       clk_data.clks = clks;
+       clk_data.clk_num = MAX_CLKS;
+       of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
+       return;
+fail:
+       iounmap(base);
+}
+CLK_OF_DECLARE(asm9260_acc, "alphascale,asm9260-clock-controller",
+               asm9260_acc_init);

Where is the DT binding definition for this clock provider?

Thanks,
Mike

do you mean this patch?
http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/293147.html
(probably not last version)
Should i resend it to you?

-- 
Regards,
Oleksij

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