powerpc/512x: clk: minor comment updates

adjust (expand on or move) a few comments,
add markers for easier navigation around helpers
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

arch/powerpc/platforms/512x/clock-commonclk.c

@@ -76,6 +76,8 @@ static struct clk_onecell_data clk_data;
 static struct mpc512x_ccm __iomem *clkregs;
 static DEFINE_SPINLOCK(clklock);
 
+/* common clk API wrappers {{{ */
+
 /* convenience wrappers around the common clk API */
 static inline struct clk *mpc512x_clk_fixed(const char *name, int rate)
 {
@@ -139,6 +141,8 @@ static inline struct clk *mpc512x_clk_muxed(const char *name,
 				reg, pos, len, muxflags, &clklock);
 }
 
+/* }}} common clk API wrappers */
+
 /* helper to isolate a bit field from a register */
 static inline int get_bit_field(uint32_t __iomem *reg, uint8_t pos, uint8_t len)
 {
@@ -308,6 +312,8 @@ static void mpc512x_clk_setup_ref_clock(struct device_node *np, int bus_freq,
 	}
 }
 
+/* MCLK helpers {{{ */
+
 /*
  * helper code for the MCLK subtree setup
  *
@@ -338,8 +344,8 @@ static void mpc512x_clk_setup_ref_clock(struct device_node *np, int bus_freq,
 
 /*
  * note that this declaration raises a checkpatch warning, but
- * it's the very data type which <linux/clk-provider.h> expects,
- * making this declaration pass checkpatch will break compilation
+ * it's the very data type dictated by <linux/clk-provider.h>,
+ * "fixing" this warning will break compilation
  */
 static const char *parent_names_mux0[] = {
 	"sys", "ref", "psc-mclk-in", "spdif-tx",
@@ -512,6 +518,8 @@ static void mpc512x_clk_setup_mclk(struct mclk_setup_data *entry, size_t idx)
 	}
 }
 
+/* }}} MCLK helpers */
+
 static void mpc512x_clk_setup_clock_tree(struct device_node *np, int busfreq)
 {
 	int sys_mul, sys_div, ips_div;
@@ -549,8 +557,8 @@ static void mpc512x_clk_setup_clock_tree(struct device_node *np, int busfreq)
 	clks[MPC512x_CLK_IPS] = mpc512x_clk_divtable("ips", "csb",
 						     &clkregs->scfr1, 23, 3,
 						     divtab_2346);
-
 	/* now setup anything below SYS and CSB and IPS */
+
 	clks[MPC512x_CLK_DDR_UG] = mpc512x_clk_factor("ddr-ug", "sys", 1, 2);
 	clks[MPC512x_CLK_SDHC_x4] = mpc512x_clk_factor("sdhc-x4", "csb", 4, 1);
 	clks[MPC512x_CLK_SDHC_UG] = mpc512x_clk_divider("sdhc-ug", "sdhc-x4", 0,