clk: convert API to match reset/mailbox style

The following changes are made to the clock API:
* The concept of "clocks" and "peripheral clocks" are unified; each clock
  provider now implements a single set of clocks. This provides a simpler
  conceptual interface to clients, and better aligns with device tree
  clock bindings.
* Clocks are now identified with a single "struct clk", rather than
  requiring clients to store the clock provider device and clock identity
  values separately. For simple clock consumers, this isolates clients
  from internal details of the clock API.
* clk.h is split so it only contains the client/consumer API, whereas
  clk-uclass.h contains the provider API. This aligns with the recently
  added reset and mailbox APIs.
* clk_ops .of_xlate(), .request(), and .free() are added so providers
  can customize these operations if needed. This also aligns with the
  recently added reset and mailbox APIs.
* clk_disable() is added.
* All users of the current clock APIs are updated.
* Sandbox clock tests are updated to exercise clock lookup via DT, and
  clock enable/disable.
* rkclk_get_clk() is removed and replaced with standard APIs.

Buildman shows no clock-related errors for any board for which buildman
can download a toolchain.

test/py passes for sandbox (which invokes the dm clk test amongst
others).

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>

2 files changed, 44 insertions, 10 deletions

diff --git a/arch/arm/mach-rockchip/board.c b/arch/arm/mach-rockchip/board.c
index 133d66341b..816540e582 100644
--- a/arch/arm/mach-rockchip/board.c
+++ b/arch/arm/mach-rockchip/board.c
@@ -9,6 +9,7 @@
 #include <dm.h>
 #include <ram.h>
 #include <asm/io.h>
+#include <asm/arch/clock.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -54,15 +55,43 @@ void lowlevel_init(void)
 static int do_clock(cmd_tbl_t *cmdtp, int flag, int argc,
 		       char * const argv[])
 {
+	static const struct {
+		char *name;
+		int id;
+	} clks[] = {
+		{ "osc", CLK_OSC },
+		{ "apll", CLK_ARM },
+		{ "dpll", CLK_DDR },
+		{ "cpll", CLK_CODEC },
+		{ "gpll", CLK_GENERAL },
+#ifdef CONFIG_ROCKCHIP_RK3036
+		{ "mpll", CLK_NEW },
+#else
+		{ "npll", CLK_NEW },
+#endif
+	};
+	int ret, i;
 	struct udevice *dev;
 
-	for (uclass_first_device(UCLASS_CLK, &dev);
-	     dev;
-	     uclass_next_device(&dev)) {
+	ret = uclass_get_device(UCLASS_CLK, 0, &dev);
+	if (ret) {
+		printf("clk-uclass not found\n");
+		return 0;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(clks); i++) {
+		struct clk clk;
 		ulong rate;
 
-		rate = clk_get_rate(dev);
-		printf("%s: %lu\n", dev->name, rate);
+		clk.id = clks[i].id;
+		ret = clk_request(dev, &clk);
+		if (ret < 0)
+			continue;
+
+		rate = clk_get_rate(&clk);
+		printf("%s: %lu\n", clks[i].name, rate);
+
+		clk_free(&clk);
 	}
 
 	return 0;
diff --git a/arch/arm/mach-rockchip/rk3288/sdram_rk3288.c b/arch/arm/mach-rockchip/rk3288/sdram_rk3288.c
index 2e21282335..55ac73e9d2 100644
--- a/arch/arm/mach-rockchip/rk3288/sdram_rk3288.c
+++ b/arch/arm/mach-rockchip/rk3288/sdram_rk3288.c
@@ -36,7 +36,7 @@ struct chan_info {
 struct dram_info {
 	struct chan_info chan[2];
 	struct ram_info info;
-	struct udevice *ddr_clk;
+	struct clk ddr_clk;
 	struct rk3288_cru *cru;
 	struct rk3288_grf *grf;
 	struct rk3288_sgrf *sgrf;
@@ -576,7 +576,7 @@ static void dram_all_config(const struct dram_info *dram,
 	rk_clrsetreg(&dram->sgrf->soc_con2, 0x1f, sdram_params->base.stride);
 }
 
-static int sdram_init(const struct dram_info *dram,
+static int sdram_init(struct dram_info *dram,
 		      const struct rk3288_sdram_params *sdram_params)
 {
 	int channel;
@@ -592,8 +592,8 @@ static int sdram_init(const struct dram_info *dram,
 		return -E2BIG;
 	}
 
-	debug("ddr clk %s\n", dram->ddr_clk->name);
-	ret = clk_set_rate(dram->ddr_clk, sdram_params->base.ddr_freq);
+	debug("ddr clk dpll\n");
+	ret = clk_set_rate(&dram->ddr_clk, sdram_params->base.ddr_freq);
 	debug("ret=%d\n", ret);
 	if (ret) {
 		debug("Could not set DDR clock\n");
@@ -836,6 +836,7 @@ static int rk3288_dmc_probe(struct udevice *dev)
 	struct dram_info *priv = dev_get_priv(dev);
 	struct regmap *map;
 	int ret;
+	struct udevice *dev_clk;
 
 	map = syscon_get_regmap_by_driver_data(ROCKCHIP_SYSCON_NOC);
 	if (IS_ERR(map))
@@ -856,7 +857,11 @@ static int rk3288_dmc_probe(struct udevice *dev)
 	priv->chan[1].pctl = regmap_get_range(map, 2);
 	priv->chan[1].publ = regmap_get_range(map, 3);
 
-	ret = uclass_get_device(UCLASS_CLK, CLK_DDR, &priv->ddr_clk);
+	ret = uclass_get_device(UCLASS_CLK, 0, &dev_clk);
+	if (ret)
+		return ret;
+	priv->ddr_clk.id = CLK_DDR;
+	ret = clk_request(dev_clk, &priv->ddr_clk);
 	if (ret)
 		return ret;