rockchip: rk3368: Add clock driver

Add driver to setup the various PLLs and peripheral
clocks on the RK3368.

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/clk/rockchip/Makefile b/drivers/clk/rockchip/Makefile
index 1091a76..8dc60f8 100644
--- a/drivers/clk/rockchip/Makefile
+++ b/drivers/clk/rockchip/Makefile
@@ -8,4 +8,5 @@
 obj-$(CONFIG_ROCKCHIP_RK3188) += clk_rk3188.o
 obj-$(CONFIG_ROCKCHIP_RK3288) += clk_rk3288.o
 obj-$(CONFIG_ROCKCHIP_RK3328) += clk_rk3328.o
+obj-$(CONFIG_ROCKCHIP_RK3368) += clk_rk3368.o
 obj-$(CONFIG_ROCKCHIP_RK3399) += clk_rk3399.o
diff --git a/drivers/clk/rockchip/clk_rk3368.c b/drivers/clk/rockchip/clk_rk3368.c
new file mode 100644
index 0000000..52cad38
--- /dev/null
+++ b/drivers/clk/rockchip/clk_rk3368.c
@@ -0,0 +1,291 @@
+/*
+ * (C) Copyright 2017 Rockchip Electronics Co., Ltd
+ * Author: Andy Yan <andy.yan@rock-chips.com>
+ * SPDX-License-Identifier:	GPL-2.0
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm.h>
+#include <errno.h>
+#include <syscon.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/cru_rk3368.h>
+#include <asm/arch/hardware.h>
+#include <asm/io.h>
+#include <dm/lists.h>
+#include <dt-bindings/clock/rk3368-cru.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct pll_div {
+	u32 nr;
+	u32 nf;
+	u32 no;
+};
+
+#define OSC_HZ		(24 * 1000 * 1000)
+#define APLL_L_HZ	(800 * 1000 * 1000)
+#define APLL_B_HZ	(816 * 1000 * 1000)
+#define GPLL_HZ		(576 * 1000 * 1000)
+#define CPLL_HZ		(400 * 1000 * 1000)
+
+#define RATE_TO_DIV(input_rate, output_rate) \
+		((input_rate) / (output_rate) - 1);
+
+#define DIV_TO_RATE(input_rate, div)    ((input_rate) / ((div) + 1))
+
+#define PLL_DIVISORS(hz, _nr, _no) { \
+	.nr = _nr, .nf = (u32)((u64)hz * _nr * _no / OSC_HZ), .no = _no}; \
+	_Static_assert(((u64)hz * _nr * _no / OSC_HZ) * OSC_HZ /\
+		       (_nr * _no) == hz, #hz "Hz cannot be hit with PLL " \
+		       "divisors on line " __stringify(__LINE__));
+
+static const struct pll_div apll_l_init_cfg = PLL_DIVISORS(APLL_L_HZ, 12, 2);
+static const struct pll_div apll_b_init_cfg = PLL_DIVISORS(APLL_B_HZ, 1, 2);
+static const struct pll_div gpll_init_cfg = PLL_DIVISORS(GPLL_HZ, 1, 2);
+static const struct pll_div cpll_init_cfg = PLL_DIVISORS(CPLL_HZ, 1, 6);
+
+/* Get pll rate by id */
+static uint32_t rkclk_pll_get_rate(struct rk3368_cru *cru,
+				   enum rk3368_pll_id pll_id)
+{
+	uint32_t nr, no, nf;
+	uint32_t con;
+	struct rk3368_pll *pll = &cru->pll[pll_id];
+
+	con = readl(&pll->con3);
+
+	switch ((con & PLL_MODE_MASK) >> PLL_MODE_SHIFT) {
+	case PLL_MODE_SLOW:
+		return OSC_HZ;
+	case PLL_MODE_NORMAL:
+		con = readl(&pll->con0);
+		no = ((con & PLL_OD_MASK) >> PLL_OD_SHIFT) + 1;
+		nr = ((con & PLL_NR_MASK) >> PLL_NR_SHIFT) + 1;
+		con = readl(&pll->con1);
+		nf = ((con & PLL_NF_MASK) >> PLL_NF_SHIFT) + 1;
+
+		return (24 * nf / (nr * no)) * 1000000;
+	case PLL_MODE_DEEP_SLOW:
+	default:
+		return 32768;
+	}
+}
+
+static int rkclk_set_pll(struct rk3368_cru *cru, enum rk3368_pll_id pll_id,
+			 const struct pll_div *div, bool has_bwadj)
+{
+	struct rk3368_pll *pll = &cru->pll[pll_id];
+	/* All PLLs have same VCO and output frequency range restrictions*/
+	uint vco_hz = OSC_HZ / 1000 * div->nf / div->nr * 1000;
+	uint output_hz = vco_hz / div->no;
+
+	debug("PLL at %p: nf=%d, nr=%d, no=%d, vco=%u Hz, output=%u Hz\n",
+	      pll, div->nf, div->nr, div->no, vco_hz, output_hz);
+
+	/* enter slow mode and reset pll */
+	rk_clrsetreg(&pll->con3, PLL_MODE_MASK | PLL_RESET_MASK,
+		     PLL_RESET << PLL_RESET_SHIFT);
+
+	rk_clrsetreg(&pll->con0, PLL_NR_MASK | PLL_OD_MASK,
+		     ((div->nr - 1) << PLL_NR_SHIFT) |
+		     ((div->no - 1) << PLL_OD_SHIFT));
+	writel((div->nf - 1) << PLL_NF_SHIFT, &pll->con1);
+	udelay(10);
+
+	/* return from reset */
+	rk_clrreg(&pll->con3, PLL_RESET_MASK);
+
+	/* waiting for pll lock */
+	while (!(readl(&pll->con1) & PLL_LOCK_STA))
+		udelay(1);
+
+	rk_clrsetreg(&pll->con3, PLL_MODE_MASK,
+		     PLL_MODE_NORMAL << PLL_MODE_SHIFT);
+
+	return 0;
+}
+
+static void rkclk_init(struct rk3368_cru *cru)
+{
+	u32 apllb, aplll, dpll, cpll, gpll;
+
+	rkclk_set_pll(cru, APLLB, &apll_b_init_cfg, false);
+	rkclk_set_pll(cru, APLLL, &apll_l_init_cfg, false);
+	rkclk_set_pll(cru, GPLL, &gpll_init_cfg, false);
+	rkclk_set_pll(cru, CPLL, &cpll_init_cfg, false);
+
+	apllb = rkclk_pll_get_rate(cru, APLLB);
+	aplll = rkclk_pll_get_rate(cru, APLLL);
+	dpll = rkclk_pll_get_rate(cru, DPLL);
+	cpll = rkclk_pll_get_rate(cru, CPLL);
+	gpll = rkclk_pll_get_rate(cru, GPLL);
+
+	debug("%s apllb(%d) apll(%d) dpll(%d) cpll(%d) gpll(%d)\n",
+	       __func__, apllb, aplll, dpll, cpll, gpll);
+}
+
+static ulong rk3368_mmc_get_clk(struct rk3368_cru *cru, uint clk_id)
+{
+	u32 div, con, con_id, rate;
+	u32 pll_rate;
+
+	switch (clk_id) {
+	case SCLK_SDMMC:
+		con_id = 50;
+		break;
+	case SCLK_EMMC:
+		con_id = 51;
+		break;
+	case SCLK_SDIO0:
+		con_id = 48;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	con = readl(&cru->clksel_con[con_id]);
+	switch ((con & MMC_PLL_SEL_MASK) >> MMC_PLL_SEL_SHIFT) {
+	case MMC_PLL_SEL_GPLL:
+		pll_rate = rkclk_pll_get_rate(cru, GPLL);
+		break;
+	case MMC_PLL_SEL_24M:
+		pll_rate = OSC_HZ;
+		break;
+	case MMC_PLL_SEL_CPLL:
+	case MMC_PLL_SEL_USBPHY_480M:
+	default:
+		return -EINVAL;
+	}
+	div = (con & MMC_CLK_DIV_MASK) >> MMC_CLK_DIV_SHIFT;
+	rate = DIV_TO_RATE(pll_rate, div);
+
+	return rate >> 1;
+}
+
+static ulong rk3368_mmc_set_clk(struct rk3368_cru *cru,
+				ulong clk_id, ulong rate)
+{
+	u32 div;
+	u32 con_id;
+	u32 gpll_rate = rkclk_pll_get_rate(cru, GPLL);
+
+	div = RATE_TO_DIV(gpll_rate, rate << 1);
+
+	switch (clk_id) {
+	case SCLK_SDMMC:
+		con_id = 50;
+		break;
+	case SCLK_EMMC:
+		con_id = 51;
+		break;
+	case SCLK_SDIO0:
+		con_id = 48;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (div > 0x3f) {
+		div = RATE_TO_DIV(OSC_HZ, rate);
+		rk_clrsetreg(&cru->clksel_con[con_id],
+			     MMC_PLL_SEL_MASK | MMC_CLK_DIV_MASK,
+			     (MMC_PLL_SEL_24M << MMC_PLL_SEL_SHIFT) |
+			     (div << MMC_CLK_DIV_SHIFT));
+	} else {
+		rk_clrsetreg(&cru->clksel_con[con_id],
+			     MMC_PLL_SEL_MASK | MMC_CLK_DIV_MASK,
+			     (MMC_PLL_SEL_GPLL << MMC_PLL_SEL_SHIFT) |
+			     div << MMC_CLK_DIV_SHIFT);
+	}
+
+	return rk3368_mmc_get_clk(cru, clk_id);
+}
+
+static ulong rk3368_clk_get_rate(struct clk *clk)
+{
+	struct rk3368_clk_priv *priv = dev_get_priv(clk->dev);
+	ulong rate = 0;
+
+	debug("%s id:%ld\n", __func__, clk->id);
+	switch (clk->id) {
+	case HCLK_SDMMC:
+	case HCLK_EMMC:
+		rate = rk3368_mmc_get_clk(priv->cru, clk->id);
+		break;
+	default:
+		return -ENOENT;
+	}
+
+	return rate;
+}
+
+static ulong rk3368_clk_set_rate(struct clk *clk, ulong rate)
+{
+	struct rk3368_clk_priv *priv = dev_get_priv(clk->dev);
+	ulong ret = 0;
+
+	debug("%s id:%ld rate:%ld\n", __func__, clk->id, rate);
+	switch (clk->id) {
+	case SCLK_SDMMC:
+	case SCLK_EMMC:
+		ret = rk3368_mmc_set_clk(priv->cru, clk->id, rate);
+		break;
+	default:
+		return -ENOENT;
+	}
+
+	return ret;
+}
+
+static struct clk_ops rk3368_clk_ops = {
+	.get_rate = rk3368_clk_get_rate,
+	.set_rate = rk3368_clk_set_rate,
+};
+
+static int rk3368_clk_probe(struct udevice *dev)
+{
+	struct rk3368_clk_priv *priv = dev_get_priv(dev);
+
+	rkclk_init(priv->cru);
+
+	return 0;
+}
+
+static int rk3368_clk_ofdata_to_platdata(struct udevice *dev)
+{
+	struct rk3368_clk_priv *priv = dev_get_priv(dev);
+
+	priv->cru = (struct rk3368_cru *)devfdt_get_addr(dev);
+
+	return 0;
+}
+
+static int rk3368_clk_bind(struct udevice *dev)
+{
+	int ret;
+
+	/* The reset driver does not have a device node, so bind it here */
+	ret = device_bind_driver(gd->dm_root, "rk3368_sysreset", "reset", &dev);
+	if (ret)
+		error("bind RK3368 reset driver failed: ret=%d\n", ret);
+
+	return ret;
+}
+
+static const struct udevice_id rk3368_clk_ids[] = {
+	{ .compatible = "rockchip,rk3368-cru" },
+	{ }
+};
+
+U_BOOT_DRIVER(rockchip_rk3368_cru) = {
+	.name		= "rockchip_rk3368_cru",
+	.id		= UCLASS_CLK,
+	.of_match	= rk3368_clk_ids,
+	.priv_auto_alloc_size = sizeof(struct rk3368_cru),
+	.ofdata_to_platdata = rk3368_clk_ofdata_to_platdata,
+	.ops		= &rk3368_clk_ops,
+	.bind		= rk3368_clk_bind,
+	.probe		= rk3368_clk_probe,
+};