Re: [PATCH v5 2/2] clk: add artpec-6 clock controller

From: Lars Persson
Date: Mon Apr 04 2016 - 04:24:51 EST




On 04/02/2016 03:39 AM, Stephen Boyd wrote:
On 03/31, Lars Persson wrote:
diff --git a/drivers/clk/axis/Makefile b/drivers/clk/axis/Makefile
new file mode 100644
index 0000000..628c9d3
--- /dev/null
+++ b/drivers/clk/axis/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_MACH_ARTPEC6) += clk-artpec6.o
diff --git a/drivers/clk/axis/clk-artpec6.c b/drivers/clk/axis/clk-artpec6.c
new file mode 100644
index 0000000..cf716f1
--- /dev/null

[snip]

+
+ /* Read PLL1 factors configured by boot strap pins. */
+ pll_mode = (readl(clkdata->syscon_base) >> 6) & 3;
+ switch (pll_mode) {
+ case 0: /* DDR3-2133 mode */
+ pll_m = 4;
+ pll_n = 85;
+ break;
+ case 1: /* DDR3-1866 mode */
+ pll_m = 6;
+ pll_n = 112;
+ break;
+ case 2: /* DDR3-1600 mode */
+ pll_m = 4;
+ pll_n = 64;
+ break;
+ case 3: /* DDR3-1333 mode */
+ pll_m = 8;
+ pll_n = 106;
+ break;
+ }
+
+ clkdata->clk_table[ARTPEC6_CLK_CPU] =
+ clk_register_fixed_factor(NULL, "cpu", sys_refclk_name, 0, pll_n,
+ pll_m);
+ clkdata->clk_table[ARTPEC6_CLK_CPU_PERIPH] =
+ clk_register_fixed_factor(NULL, "cpu_periph", "cpu", 0, 1, 2);
+
+ /* EPROBE_DEFER on the apb_clock is not handled in amba devices. */

Shouldn't we fix that then?

Marek Szyprowski recently tried to fix this, but Russel NAKed the change due to userspace breakage:
https://lkml.org/lkml/2016/2/15/555



+ clkdata->clk_table[ARTPEC6_CLK_UART_PCLK] =
+ clk_register_fixed_factor(NULL, "uart_pclk", "cpu", 0, 1, 8);
+ clkdata->clk_table[ARTPEC6_CLK_UART_REFCLK] =
+ clk_register_fixed_rate(NULL, "uart_ref", sys_refclk_name, 0,
+ 50000000);