[PATCH] clk: ppc-corenet: Add support for the FMD clock
Scott Wood
scottwood at freescale.com
Thu Feb 26 10:44:11 AEDT 2015
On Tue, 2015-01-20 at 14:03 +0200, Igal.Liberman wrote:
> +static u8 get_fm_clk_parent(struct clk_hw *hw)
> +{
> + struct ccsr_guts __iomem *guts_regs = NULL;
> + struct device_node *guts;
> + uint32_t reg = 0;
> + int clk_src = 0;
> + int fm_clk_select = -EINVAL;
> + int fm_id = 0;
> +
> + guts = of_find_matching_node(NULL, guts_device_ids);
> + if (!guts) {
> + pr_err("could not find GUTS node\n");
> + return -EINVAL;
> + }
Error message lacks context (here and elsewhere).
Why are you going this on demand rather than in an init function
(specifically, a CLK_OF_DECLARE)? You should not register this clock
handler in the first place if the hardware doesn't exist.
-EINVAL doesn't fit in u8. Neither would the more appropriate -ENODEV.
> + guts_regs = of_iomap(guts, 0);
> + of_node_put(guts);
> + if (!guts_regs) {
> + pr_err("ioremap of GUTS node failed\n");
> + return -EINVAL;
> + }
> +
> + if (!strcmp(__clk_get_name(hw->clk), "fm1-clk"))
> + fm_id = 1;
> +
> + /* The FM clock provider is SoC dependent and it's determened by the
determined
> + * reset configuration word (RCW). We need to map the RCW options to
> + * the order of the providers in the device tree.
> + * This code makes assumptions about the clock provider order:
> + * In the PXXXX family:
> + * 0 - platform clock/2
> + * 1 - PLLx /2
> + * 2 - PLLx /4 (if possible).
> + * In B/T family:
> + * The same order in which the clock providers are described in
> + * the Reference Manual, starting from 0.
This belongs in a device tree binding document and should not
incorporate portions of the reference manual by reference -- what if a
new version of the reference manual changes the order in which clock
providers are described? Or do you mean that the order corresponds to a
register value?
> + *
> + * In a case of only one possible provider, the index is 0.
> + */
> +
> + if (of_device_is_compatible(guts, "fsl,p1023-guts") ||
> + of_device_is_compatible(guts, "fsl,t1040-device-config"))
> + /* P1023 and T1040 have only one optional clock source */
> + fm_clk_select = 0;
> + else if (of_device_is_compatible(guts, "fsl,p2041-device-config") ||
> + of_device_is_compatible(guts, "fsl,p3041-device-config") ||
> + of_device_is_compatible(guts, "fsl,p4080-device-config")) {
> + /* Read RCW*/
/* Read RCW */
> @@ -352,3 +601,4 @@ CLK_OF_DECLARE(qoriq_core_mux_1, "fsl,qoriq-core-mux-1.0", core_mux_init);
> CLK_OF_DECLARE(qoriq_core_mux_2, "fsl,qoriq-core-mux-2.0", core_mux_init);
> CLK_OF_DECLARE(qoriq_pltfrm_pll_1, "fsl,qoriq-platform-pll-1.0", pltfrm_pll_init);
> CLK_OF_DECLARE(qoriq_pltfrm_pll_2, "fsl,qoriq-platform-pll-2.0", pltfrm_pll_init);
> +CLK_OF_DECLARE(qoriq_fm_mux, "fsl,fman-clk-mux", fm_mux_init);
Where is the binding for this node?
-Scott
More information about the Linuxppc-dev
mailing list