On Tue, Mar 15, 2011 at 01:37:31AM -0600, Grant Likely wrote:
On Tue, Mar 08, 2011 at 12:22:10AM +0800, Shawn Guo wrote:
This patch is to change the static clock creating and registering to the dynamic way, which scans dt clock nodes, associate clk with device_node, and then add them to clkdev accordingly.
Signed-off-by: Shawn Guo shawn.guo@linaro.org
arch/arm/mach-mx5/clock-mx51-mx53.c | 436 +++++++++++++++++++++++++++++++++-- 1 files changed, 422 insertions(+), 14 deletions(-)
diff --git a/arch/arm/mach-mx5/clock-mx51-mx53.c b/arch/arm/mach-mx5/clock-mx51-mx53.c index dedb7f9..1940171 100644 --- a/arch/arm/mach-mx5/clock-mx51-mx53.c +++ b/arch/arm/mach-mx5/clock-mx51-mx53.c @@ -135,6 +135,9 @@ static inline u32 _get_mux(struct clk *parent, struct clk *m0, static inline void __iomem *_mx51_get_pll_base(struct clk *pll) { +#ifdef CONFIG_OF
- return pll->pll_base;
+#else if (pll == &pll1_main_clk) return MX51_DPLL1_BASE; else if (pll == &pll2_sw_clk) @@ -145,6 +148,7 @@ static inline void __iomem *_mx51_get_pll_base(struct clk *pll) BUG(); return NULL; +#endif } static inline void __iomem *_mx53_get_pll_base(struct clk *pll) @@ -1439,33 +1443,437 @@ int __init mx53_clocks_init(unsigned long ckil, unsigned long osc, return 0; } +/*
- Dynamically create and register clks per dt nodes
- */
#ifdef CONFIG_OF -static struct clk *mx5_dt_clk_get(struct device_node *np,
const char *output_id, void *data)
+#define ALLOC_CLK_LOOKUP() \
- struct clk_lookup *cl; \
- struct clk *clk; \
- int ret; \
\- do { \
cl = kzalloc(sizeof(*cl) + sizeof(*clk), GFP_KERNEL); \if (!cl) \return -ENOMEM; \clk = (struct clk *) (cl + 1); \\clk->parent = mx5_get_source_clk(node); \clk->secondary = mx5_get_source_clk(node); \- } while (0)
+#define ADD_CLK_LOOKUP() \
- do { \
node->data = clk; \cl->dev_id = of_get_property(node, \"clock-outputs", NULL); \cl->con_id = of_get_property(node, \"clock-alias", NULL); \if (!cl->dev_id && !cl->con_id) { \ret = -EINVAL; \goto out_kfree; \} \cl->clk = clk; \clkdev_add(cl); \\return 0; \\- out_kfree: \
kfree(cl); \return ret; \- } while (0)
Yikes! Doing this as a macro will be a nightmare for debugging. This needs refactoring into functions.
+static unsigned long get_fixed_clk_rate(struct clk *clk) {
- return data;
- return clk->rate;
} -static __init void mx5_dt_scan_clks(void) +static __init int mx5_scan_fixed_clks(void) { struct device_node *node;
- struct clk_lookup *cl; struct clk *clk;
- const char *id;
- int rc;
- const __be32 *rate;
- int ret = 0;
- for_each_compatible_node(node, NULL, "clock") {
id = of_get_property(node, "clock-outputs", NULL);if (!id)
- for_each_compatible_node(node, NULL, "fixed-clock") {
cl = kzalloc(sizeof(*cl) + sizeof(*clk), GFP_KERNEL);if (!cl) {ret = -ENOMEM;break;}clk = (struct clk *) (cl + 1);rate = of_get_property(node, "clock-frequency", NULL);if (!rate) {kfree(cl); continue;}clk->rate = be32_to_cpu(*rate);clk->get_rate = get_fixed_clk_rate;node->data = clk;
clk = clk_get_sys(id, NULL);if (IS_ERR(clk))
cl->dev_id = of_get_property(node, "clock-outputs", NULL);cl->con_id = of_get_property(node, "clock-alias", NULL);As discussed briefly earlier, clock-alias looks like it is encoding Linux-specific implementation details into the device tree, and it shouldn't be necessary when explicit links to clock providers are supplied in the device tree.
if (!cl->dev_id && !cl->con_id) {kfree(cl); continue;}cl->clk = clk;clkdev_add(cl);- }
- return ret;
+}
+static struct clk *mx5_prop_name_to_clk(struct device_node *node,
const char *prop_name)+{
- struct device_node *provnode;
- struct clk *clk;
- const void *prop;
- u32 provhandle;
- prop = of_get_property(node, prop_name, NULL);
- if (!prop)
return NULL;- provhandle = be32_to_cpup(prop);
- provnode = of_find_node_by_phandle(provhandle);
- if (!provnode)
return NULL;- clk = provnode->data;
- of_node_put(provnode);
- return clk;
+}
+static inline struct clk *mx5_get_source_clk(struct device_node *node) +{
- return mx5_prop_name_to_clk(node, "clock-source");
+}
+static inline struct clk *mx5_get_depend_clk(struct device_node *node) +{
- return mx5_prop_name_to_clk(node, "clock-depend");
+}
Ditto here. 'clock-depend' seems to be Linux specifc. I need to look at the usage model for these properties.
This is not Linux but hardware specific. Let's look at the eSDHC1 example below.
esdhc1_clk: esdhc@0 { compatible = "fsl,mxc-clock"; reg = <0>; clock-outputs = "sdhci-esdhc-imx.0"; clock-source = <&pll2_sw_clk>; clock-depend = <&esdhc1_ipg_clk>; };
We have esdhc1_clk added to clkdev standing for the clock for hardware block eSDHC1. This clock is actually the serial clock of eSDHC1, while eSDHC1 internal working clock esdhc1_ipg_clk has also to be on to get the block functional.