clk: zynq: Add zynq clock framework driver

Add a clock framework driver for the zynq platform. The driver is based
on the platform zynq clock driver but reworked to use static functions
instead of run-time generated objects even for unused clocks.
Additionally the CONFIG_ZYNQ_PS_CLK_FREQ is replaced by the
ps-clk-frequency from the device tree.

Signed-off-by: Stefan Herbrechtsmeier <stefan.herbrechtsmeier@weidmueller.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

drivers/clk/Kconfig

@@ -28,6 +28,14 @@ config CLK_BOSTON
 	help
 	  Enable this to support the clocks
 
+config CLK_ZYNQ
+	bool "Enable clock driver support for Zynq"
+	depends on CLK && ARCH_ZYNQ
+	default y
+	help
+	  This clock driver adds support for clock realted settings for
+	  Zynq platform.
+
 config CLK_ZYNQMP
 	bool "Enable clock driver support for ZynqMP"
 	depends on ARCH_ZYNQMP

drivers/clk/Makefile

@@ -10,6 +10,7 @@ obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
 obj-$(CONFIG_SANDBOX) += clk_sandbox.o
 obj-$(CONFIG_SANDBOX) += clk_sandbox_test.o
 obj-$(CONFIG_MACH_PIC32) += clk_pic32.o
+obj-$(CONFIG_CLK_ZYNQ) += clk_zynq.o
 obj-$(CONFIG_CLK_ZYNQMP) += clk_zynqmp.o
 
 obj-y += tegra/

drivers/clk/clk_zynq.c

@@ -0,0 +1,459 @@
+/*
+ * Copyright (C) 2017 Weidmüller Interface GmbH & Co. KG
+ * Stefan Herbrechtsmeier <stefan.herbrechtsmeier@weidmueller.com>
+ *
+ * Copyright (C) 2013 Soren Brinkmann <soren.brinkmann@xilinx.com>
+ * Copyright (C) 2013 Xilinx, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm.h>
+#include <dm/lists.h>
+#include <errno.h>
+#include <asm/io.h>
+#include <asm/arch/clk.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/sys_proto.h>
+
+/* Register bitfield defines */
+#define PLLCTRL_FBDIV_MASK	0x7f000
+#define PLLCTRL_FBDIV_SHIFT	12
+#define PLLCTRL_BPFORCE_MASK	(1 << 4)
+#define PLLCTRL_PWRDWN_MASK	2
+#define PLLCTRL_PWRDWN_SHIFT	1
+#define PLLCTRL_RESET_MASK	1
+#define PLLCTRL_RESET_SHIFT	0
+
+#define ZYNQ_CLK_MAXDIV		0x3f
+#define CLK_CTRL_DIV1_SHIFT	20
+#define CLK_CTRL_DIV1_MASK	(ZYNQ_CLK_MAXDIV << CLK_CTRL_DIV1_SHIFT)
+#define CLK_CTRL_DIV0_SHIFT	8
+#define CLK_CTRL_DIV0_MASK	(ZYNQ_CLK_MAXDIV << CLK_CTRL_DIV0_SHIFT)
+#define CLK_CTRL_SRCSEL_SHIFT	4
+#define CLK_CTRL_SRCSEL_MASK	(0x3 << CLK_CTRL_SRCSEL_SHIFT)
+
+#define CLK_CTRL_DIV2X_SHIFT	26
+#define CLK_CTRL_DIV2X_MASK	(ZYNQ_CLK_MAXDIV << CLK_CTRL_DIV2X_SHIFT)
+#define CLK_CTRL_DIV3X_SHIFT	20
+#define CLK_CTRL_DIV3X_MASK	(ZYNQ_CLK_MAXDIV << CLK_CTRL_DIV3X_SHIFT)
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#ifndef CONFIG_SPL_BUILD
+enum zynq_clk_rclk {mio_clk, emio_clk};
+#endif
+
+struct zynq_clk_priv {
+	ulong ps_clk_freq;
+};
+
+static void *zynq_clk_get_register(enum zynq_clk id)
+{
+	switch (id) {
+	case armpll_clk:
+		return &slcr_base->arm_pll_ctrl;
+	case ddrpll_clk:
+		return &slcr_base->ddr_pll_ctrl;
+	case iopll_clk:
+		return &slcr_base->io_pll_ctrl;
+	case lqspi_clk:
+		return &slcr_base->lqspi_clk_ctrl;
+	case smc_clk:
+		return &slcr_base->smc_clk_ctrl;
+	case pcap_clk:
+		return &slcr_base->pcap_clk_ctrl;
+	case sdio0_clk ... sdio1_clk:
+		return &slcr_base->sdio_clk_ctrl;
+	case uart0_clk ... uart1_clk:
+		return &slcr_base->uart_clk_ctrl;
+	case spi0_clk ... spi1_clk:
+		return &slcr_base->spi_clk_ctrl;
+#ifndef CONFIG_SPL_BUILD
+	case dci_clk:
+		return &slcr_base->dci_clk_ctrl;
+	case gem0_clk:
+		return &slcr_base->gem0_clk_ctrl;
+	case gem1_clk:
+		return &slcr_base->gem1_clk_ctrl;
+	case fclk0_clk:
+		return &slcr_base->fpga0_clk_ctrl;
+	case fclk1_clk:
+		return &slcr_base->fpga1_clk_ctrl;
+	case fclk2_clk:
+		return &slcr_base->fpga2_clk_ctrl;
+	case fclk3_clk:
+		return &slcr_base->fpga3_clk_ctrl;
+	case can0_clk ... can1_clk:
+		return &slcr_base->can_clk_ctrl;
+	case dbg_trc_clk ... dbg_apb_clk:
+		/* fall through */
+#endif
+	default:
+		return &slcr_base->dbg_clk_ctrl;
+	}
+}
+
+static enum zynq_clk zynq_clk_get_cpu_pll(u32 clk_ctrl)
+{
+	u32 srcsel = (clk_ctrl & CLK_CTRL_SRCSEL_MASK) >> CLK_CTRL_SRCSEL_SHIFT;
+
+	switch (srcsel) {
+	case 2:
+		return ddrpll_clk;
+	case 3:
+		return iopll_clk;
+	case 0 ... 1:
+	default:
+		return armpll_clk;
+	}
+}
+
+static enum zynq_clk zynq_clk_get_peripheral_pll(u32 clk_ctrl)
+{
+	u32 srcsel = (clk_ctrl & CLK_CTRL_SRCSEL_MASK) >> CLK_CTRL_SRCSEL_SHIFT;
+
+	switch (srcsel) {
+	case 2:
+		return armpll_clk;
+	case 3:
+		return ddrpll_clk;
+	case 0 ... 1:
+	default:
+		return iopll_clk;
+	}
+}
+
+static ulong zynq_clk_get_pll_rate(struct zynq_clk_priv *priv, enum zynq_clk id)
+{
+	u32 clk_ctrl, reset, pwrdwn, mul, bypass;
+
+	clk_ctrl = readl(zynq_clk_get_register(id));
+
+	reset = (clk_ctrl & PLLCTRL_RESET_MASK) >> PLLCTRL_RESET_SHIFT;
+	pwrdwn = (clk_ctrl & PLLCTRL_PWRDWN_MASK) >> PLLCTRL_PWRDWN_SHIFT;
+	if (reset || pwrdwn)
+		return 0;
+
+	bypass = clk_ctrl & PLLCTRL_BPFORCE_MASK;
+	if (bypass)
+		mul = 1;
+	else
+		mul = (clk_ctrl & PLLCTRL_FBDIV_MASK) >> PLLCTRL_FBDIV_SHIFT;
+
+	return priv->ps_clk_freq * mul;
+}
+
+#ifndef CONFIG_SPL_BUILD
+static enum zynq_clk_rclk zynq_clk_get_gem_rclk(enum zynq_clk id)
+{
+	u32 clk_ctrl, srcsel;
+
+	if (id == gem0_clk)
+		clk_ctrl = readl(&slcr_base->gem0_rclk_ctrl);
+	else
+		clk_ctrl = readl(&slcr_base->gem1_rclk_ctrl);
+
+	srcsel = (clk_ctrl & CLK_CTRL_SRCSEL_MASK) >> CLK_CTRL_SRCSEL_SHIFT;
+	if (srcsel)
+		return emio_clk;
+	else
+		return mio_clk;
+}
+#endif
+
+static ulong zynq_clk_get_cpu_rate(struct zynq_clk_priv *priv, enum zynq_clk id)
+{
+	u32 clk_621, clk_ctrl, div;
+	enum zynq_clk pll;
+
+	clk_ctrl = readl(&slcr_base->arm_clk_ctrl);
+
+	div = (clk_ctrl & CLK_CTRL_DIV0_MASK) >> CLK_CTRL_DIV0_SHIFT;
+
+	switch (id) {
+	case cpu_1x_clk:
+		div *= 2;
+		/* fall through */
+	case cpu_2x_clk:
+		clk_621 = readl(&slcr_base->clk_621_true) & 1;
+		div *= 2 + clk_621;
+		break;
+	case cpu_3or2x_clk:
+		div *= 2;
+		/* fall through */
+	case cpu_6or4x_clk:
+		break;
+	default:
+		return 0;
+	}
+
+	pll = zynq_clk_get_cpu_pll(clk_ctrl);
+
+	return DIV_ROUND_CLOSEST(zynq_clk_get_pll_rate(priv, pll), div);
+}
+
+#ifndef CONFIG_SPL_BUILD
+static ulong zynq_clk_get_ddr2x_rate(struct zynq_clk_priv *priv)
+{
+	u32 clk_ctrl, div;
+
+	clk_ctrl = readl(&slcr_base->ddr_clk_ctrl);
+
+	div = (clk_ctrl & CLK_CTRL_DIV2X_MASK) >> CLK_CTRL_DIV2X_SHIFT;
+
+	return DIV_ROUND_CLOSEST(zynq_clk_get_pll_rate(priv, ddrpll_clk), div);
+}
+#endif
+
+static ulong zynq_clk_get_ddr3x_rate(struct zynq_clk_priv *priv)
+{
+	u32 clk_ctrl, div;
+
+	clk_ctrl = readl(&slcr_base->ddr_clk_ctrl);
+
+	div = (clk_ctrl & CLK_CTRL_DIV3X_MASK) >> CLK_CTRL_DIV3X_SHIFT;
+
+	return DIV_ROUND_CLOSEST(zynq_clk_get_pll_rate(priv, ddrpll_clk), div);
+}
+
+#ifndef CONFIG_SPL_BUILD
+static ulong zynq_clk_get_dci_rate(struct zynq_clk_priv *priv)
+{
+	u32 clk_ctrl, div0, div1;
+
+	clk_ctrl = readl(&slcr_base->dci_clk_ctrl);
+
+	div0 = (clk_ctrl & CLK_CTRL_DIV0_MASK) >> CLK_CTRL_DIV0_SHIFT;
+	div1 = (clk_ctrl & CLK_CTRL_DIV1_MASK) >> CLK_CTRL_DIV1_SHIFT;
+
+	return DIV_ROUND_CLOSEST(DIV_ROUND_CLOSEST(
+		zynq_clk_get_pll_rate(priv, ddrpll_clk), div0), div1);
+}
+#endif
+
+static ulong zynq_clk_get_peripheral_rate(struct zynq_clk_priv *priv,
+					  enum zynq_clk id, bool two_divs)
+{
+	enum zynq_clk pll;
+	u32 clk_ctrl, div0;
+	u32 div1 = 1;
+
+	clk_ctrl = readl(zynq_clk_get_register(id));
+
+	div0 = (clk_ctrl & CLK_CTRL_DIV0_MASK) >> CLK_CTRL_DIV0_SHIFT;
+	if (!div0)
+		div0 = 1;
+
+#ifndef CONFIG_SPL_BUILD
+	if (two_divs) {
+		div1 = (clk_ctrl & CLK_CTRL_DIV1_MASK) >> CLK_CTRL_DIV1_SHIFT;
+		if (!div1)
+			div1 = 1;
+	}
+#endif
+
+	pll = zynq_clk_get_peripheral_pll(clk_ctrl);
+
+	return
+		DIV_ROUND_CLOSEST(
+			DIV_ROUND_CLOSEST(
+				zynq_clk_get_pll_rate(priv, pll), div0),
+			div1);
+}
+
+#ifndef CONFIG_SPL_BUILD
+static ulong zynq_clk_get_gem_rate(struct zynq_clk_priv *priv, enum zynq_clk id)
+{
+	if (zynq_clk_get_gem_rclk(id) == mio_clk)
+		return zynq_clk_get_peripheral_rate(priv, id, true);
+
+	debug("%s: gem%d emio rx clock source unknown\n", __func__,
+	      id - gem0_clk);
+
+	return -ENOSYS;
+}
+
+static unsigned long zynq_clk_calc_peripheral_two_divs(ulong rate,
+						       ulong pll_rate,
+						       u32 *div0, u32 *div1)
+{
+	long new_err, best_err = (long)(~0UL >> 1);
+	ulong new_rate, best_rate = 0;
+	u32 d0, d1;
+
+	for (d0 = 1; d0 <= ZYNQ_CLK_MAXDIV; d0++) {
+		for (d1 = 1; d1 <= ZYNQ_CLK_MAXDIV >> 1; d1++) {
+			new_rate = DIV_ROUND_CLOSEST(
+					DIV_ROUND_CLOSEST(pll_rate, d0), d1);
+			new_err = abs(new_rate - rate);
+
+			if (new_err < best_err) {
+				*div0 = d0;
+				*div1 = d1;
+				best_err = new_err;
+				best_rate = new_rate;
+			}
+		}
+	}
+
+	return best_rate;
+}
+
+static ulong zynq_clk_set_peripheral_rate(struct zynq_clk_priv *priv,
+					  enum zynq_clk id, ulong rate,
+					  bool two_divs)
+{
+	enum zynq_clk pll;
+	u32 clk_ctrl, div0 = 0, div1 = 0;
+	ulong pll_rate, new_rate;
+	u32 *reg;
+
+	reg = zynq_clk_get_register(id);
+	clk_ctrl = readl(reg);
+
+	pll = zynq_clk_get_peripheral_pll(clk_ctrl);
+	pll_rate = zynq_clk_get_pll_rate(priv, pll);
+	clk_ctrl &= ~CLK_CTRL_DIV0_MASK;
+	if (two_divs) {
+		clk_ctrl &= ~CLK_CTRL_DIV1_MASK;
+		new_rate = zynq_clk_calc_peripheral_two_divs(rate, pll_rate,
+				&div0, &div1);
+		clk_ctrl |= div1 << CLK_CTRL_DIV1_SHIFT;
+	} else {
+		div0 = DIV_ROUND_CLOSEST(pll_rate, rate);
+		if (div0 > ZYNQ_CLK_MAXDIV)
+			div0 = ZYNQ_CLK_MAXDIV;
+		new_rate = DIV_ROUND_CLOSEST(rate, div0);
+	}
+	clk_ctrl |= div0 << CLK_CTRL_DIV0_SHIFT;
+
+	zynq_slcr_unlock();
+	writel(clk_ctrl, reg);
+	zynq_slcr_lock();
+
+	return new_rate;
+}
+
+static ulong zynq_clk_set_gem_rate(struct zynq_clk_priv *priv, enum zynq_clk id,
+				   ulong rate)
+{
+	if (zynq_clk_get_gem_rclk(id) == mio_clk)
+		return zynq_clk_set_peripheral_rate(priv, id, rate, true);
+
+	debug("%s: gem%d emio rx clock source unknown\n", __func__,
+	      id - gem0_clk);
+
+	return -ENOSYS;
+}
+#endif
+
+#ifndef CONFIG_SPL_BUILD
+static ulong zynq_clk_get_rate(struct clk *clk)
+{
+	struct zynq_clk_priv *priv = dev_get_priv(clk->dev);
+	enum zynq_clk id = clk->id;
+	bool two_divs = false;
+
+	switch (id) {
+	case armpll_clk ... iopll_clk:
+		return zynq_clk_get_pll_rate(priv, id);
+	case cpu_6or4x_clk ... cpu_1x_clk:
+		return zynq_clk_get_cpu_rate(priv, id);
+	case ddr2x_clk:
+		return zynq_clk_get_ddr2x_rate(priv);
+	case ddr3x_clk:
+		return zynq_clk_get_ddr3x_rate(priv);
+	case dci_clk:
+		return zynq_clk_get_dci_rate(priv);
+	case gem0_clk ... gem1_clk:
+		return zynq_clk_get_gem_rate(priv, id);
+	case fclk0_clk ... can1_clk:
+		two_divs = true;
+		/* fall through */
+	case dbg_trc_clk ... dbg_apb_clk:
+	case lqspi_clk ... pcap_clk:
+	case sdio0_clk ... spi1_clk:
+		return zynq_clk_get_peripheral_rate(priv, id, two_divs);
+	case dma_clk:
+		return zynq_clk_get_cpu_rate(priv, cpu_2x_clk);
+	case usb0_aper_clk ... smc_aper_clk:
+		return zynq_clk_get_cpu_rate(priv, cpu_1x_clk);
+	default:
+		return -ENXIO;
+	}
+}
+
+static ulong zynq_clk_set_rate(struct clk *clk, ulong rate)
+{
+	struct zynq_clk_priv *priv = dev_get_priv(clk->dev);
+	enum zynq_clk id = clk->id;
+	bool two_divs = false;
+
+	switch (id) {
+	case gem0_clk ... gem1_clk:
+		return zynq_clk_set_gem_rate(priv, id, rate);
+	case fclk0_clk ... can1_clk:
+		two_divs = true;
+		/* fall through */
+	case lqspi_clk ... pcap_clk:
+	case sdio0_clk ... spi1_clk:
+	case dbg_trc_clk ... dbg_apb_clk:
+		return zynq_clk_set_peripheral_rate(priv, id, rate, two_divs);
+	default:
+		return -ENXIO;
+	}
+}
+#else
+static ulong zynq_clk_get_rate(struct clk *clk)
+{
+	struct zynq_clk_priv *priv = dev_get_priv(clk->dev);
+	enum zynq_clk id = clk->id;
+
+	switch (id) {
+	case cpu_6or4x_clk ... cpu_1x_clk:
+		return zynq_clk_get_cpu_rate(priv, id);
+	case ddr3x_clk:
+		return zynq_clk_get_ddr3x_rate(priv);
+	case lqspi_clk ... pcap_clk:
+	case sdio0_clk ... spi1_clk:
+		return zynq_clk_get_peripheral_rate(priv, id, 0);
+	default:
+		return -ENXIO;
+	}
+}
+#endif
+
+static struct clk_ops zynq_clk_ops = {
+	.get_rate = zynq_clk_get_rate,
+#ifndef CONFIG_SPL_BUILD
+	.set_rate = zynq_clk_set_rate,
+#endif
+};
+
+static int zynq_clk_probe(struct udevice *dev)
+{
+	struct zynq_clk_priv *priv = dev_get_priv(dev);
+
+	priv->ps_clk_freq = fdtdec_get_uint(gd->fdt_blob, dev->of_offset,
+					    "ps-clk-frequency", 33333333UL);
+
+	return 0;
+}
+
+static const struct udevice_id zynq_clk_ids[] = {
+	{ .compatible = "xlnx,ps7-clkc"},
+	{}
+};
+
+U_BOOT_DRIVER(zynq_clk) = {
+	.name		= "zynq_clk",
+	.id		= UCLASS_CLK,
+	.of_match	= zynq_clk_ids,
+	.flags		= DM_FLAG_PRE_RELOC,
+	.ops		= &zynq_clk_ops,
+	.priv_auto_alloc_size = sizeof(struct zynq_clk_priv),
+	.probe		= zynq_clk_probe,
+};