clk: agilex: Add clock driver for Agilex

Add clock manager driver for Agilex. Provides clock initialization
and get_rate functions.

agilex-clock.h is from Linux commit ID cd2e1ad12247.

Signed-off-by: Chee Hong Ang <chee.hong.ang@intel.com>
Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>
Reviewed-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
diff --git a/drivers/clk/altera/clk-agilex.c b/drivers/clk/altera/clk-agilex.c
new file mode 100644
index 0000000..5fedec5
--- /dev/null
+++ b/drivers/clk/altera/clk-agilex.c
@@ -0,0 +1,579 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Intel Corporation <www.intel.com>
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <clk-uclass.h>
+#include <dm.h>
+#include <dm/lists.h>
+#include <dm/util.h>
+#include <dt-bindings/clock/agilex-clock.h>
+
+#include <asm/arch/clock_manager.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct socfpga_clk_platdata {
+	void __iomem *regs;
+};
+
+/*
+ * function to write the bypass register which requires a poll of the
+ * busy bit
+ */
+static void clk_write_bypass_mainpll(struct socfpga_clk_platdata *plat, u32 val)
+{
+	CM_REG_WRITEL(plat, val, CLKMGR_MAINPLL_BYPASS);
+	cm_wait_for_fsm();
+}
+
+static void clk_write_bypass_perpll(struct socfpga_clk_platdata *plat, u32 val)
+{
+	CM_REG_WRITEL(plat, val, CLKMGR_PERPLL_BYPASS);
+	cm_wait_for_fsm();
+}
+
+/* function to write the ctrl register which requires a poll of the busy bit */
+static void clk_write_ctrl(struct socfpga_clk_platdata *plat, u32 val)
+{
+	CM_REG_WRITEL(plat, val, CLKMGR_CTRL);
+	cm_wait_for_fsm();
+}
+
+#define MEMBUS_MAINPLL				0
+#define MEMBUS_PERPLL				1
+#define MEMBUS_TIMEOUT				1000
+#define MEMBUS_ADDR_CLKSLICE			0x27
+#define MEMBUS_CLKSLICE_SYNC_MODE_EN		0x80
+
+static int membus_wait_for_req(struct socfpga_clk_platdata *plat, u32 pll,
+			       int timeout)
+{
+	int cnt = 0;
+	u32 req_status;
+
+	if (pll == MEMBUS_MAINPLL)
+		req_status = CM_REG_READL(plat, CLKMGR_MAINPLL_MEM);
+	else
+		req_status = CM_REG_READL(plat, CLKMGR_PERPLL_MEM);
+
+	while ((cnt < timeout) && (req_status & CLKMGR_MEM_REQ_SET_MSK)) {
+		if (pll == MEMBUS_MAINPLL)
+			req_status = CM_REG_READL(plat, CLKMGR_MAINPLL_MEM);
+		else
+			req_status = CM_REG_READL(plat, CLKMGR_PERPLL_MEM);
+		cnt++;
+	}
+
+	if (cnt >= timeout)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+static int membus_write_pll(struct socfpga_clk_platdata *plat, u32 pll,
+			    u32 addr_offset, u32 wdat, int timeout)
+{
+	u32 addr;
+	u32 val;
+
+	addr = ((addr_offset | CLKMGR_MEM_ADDR_START) & CLKMGR_MEM_ADDR_MASK);
+
+	val = (CLKMGR_MEM_REQ_SET_MSK | CLKMGR_MEM_WR_SET_MSK |
+	       (wdat << CLKMGR_MEM_WDAT_LSB_OFFSET) | addr);
+
+	if (pll == MEMBUS_MAINPLL)
+		CM_REG_WRITEL(plat, val, CLKMGR_MAINPLL_MEM);
+	else
+		CM_REG_WRITEL(plat, val, CLKMGR_PERPLL_MEM);
+
+	debug("MEMBUS: Write 0x%08x to addr = 0x%08x\n", wdat, addr);
+
+	return membus_wait_for_req(plat, pll, timeout);
+}
+
+static int membus_read_pll(struct socfpga_clk_platdata *plat, u32 pll,
+			   u32 addr_offset, u32 *rdata, int timeout)
+{
+	u32 addr;
+	u32 val;
+
+	addr = ((addr_offset | CLKMGR_MEM_ADDR_START) & CLKMGR_MEM_ADDR_MASK);
+
+	val = ((CLKMGR_MEM_REQ_SET_MSK & ~CLKMGR_MEM_WR_SET_MSK) | addr);
+
+	if (pll == MEMBUS_MAINPLL)
+		CM_REG_WRITEL(plat, val, CLKMGR_MAINPLL_MEM);
+	else
+		CM_REG_WRITEL(plat, val, CLKMGR_PERPLL_MEM);
+
+	*rdata = 0;
+
+	if (membus_wait_for_req(plat, pll, timeout))
+		return -ETIMEDOUT;
+
+	if (pll == MEMBUS_MAINPLL)
+		*rdata = CM_REG_READL(plat, CLKMGR_MAINPLL_MEMSTAT);
+	else
+		*rdata = CM_REG_READL(plat, CLKMGR_PERPLL_MEMSTAT);
+
+	debug("MEMBUS: Read 0x%08x from addr = 0x%08x\n", *rdata, addr);
+
+	return 0;
+}
+
+static u32 calc_vocalib_pll(u32 pllm, u32 pllglob)
+{
+	u32 mdiv, refclkdiv, arefclkdiv, drefclkdiv, mscnt, hscnt, vcocalib;
+
+	mdiv = pllm & CLKMGR_PLLM_MDIV_MASK;
+	arefclkdiv = (pllglob & CLKMGR_PLLGLOB_AREFCLKDIV_MASK) >>
+		      CLKMGR_PLLGLOB_AREFCLKDIV_OFFSET;
+	drefclkdiv = (pllglob & CLKMGR_PLLGLOB_DREFCLKDIV_MASK) >>
+		      CLKMGR_PLLGLOB_DREFCLKDIV_OFFSET;
+	refclkdiv = (pllglob & CLKMGR_PLLGLOB_REFCLKDIV_MASK) >>
+		     CLKMGR_PLLGLOB_REFCLKDIV_OFFSET;
+	mscnt = CLKMGR_VCOCALIB_MSCNT_CONST / (mdiv * BIT(drefclkdiv));
+	if (!mscnt)
+		mscnt = 1;
+	hscnt = (mdiv * mscnt * BIT(drefclkdiv) / refclkdiv) -
+		CLKMGR_VCOCALIB_HSCNT_CONST;
+	vcocalib = (hscnt & CLKMGR_VCOCALIB_HSCNT_MASK) |
+		   ((mscnt << CLKMGR_VCOCALIB_MSCNT_OFFSET) &
+		     CLKMGR_VCOCALIB_MSCNT_MASK);
+
+	/* Dump all the pll calibration settings for debug purposes */
+	debug("mdiv          : %d\n", mdiv);
+	debug("arefclkdiv    : %d\n", arefclkdiv);
+	debug("drefclkdiv    : %d\n", drefclkdiv);
+	debug("refclkdiv     : %d\n", refclkdiv);
+	debug("mscnt         : %d\n", mscnt);
+	debug("hscnt         : %d\n", hscnt);
+	debug("vcocalib      : 0x%08x\n", vcocalib);
+
+	return vcocalib;
+}
+
+/*
+ * Setup clocks while making no assumptions about previous state of the clocks.
+ */
+static void clk_basic_init(struct udevice *dev,
+			   const struct cm_config * const cfg)
+{
+	struct socfpga_clk_platdata *plat = dev_get_platdata(dev);
+	u32 vcocalib;
+	u32 rdata;
+
+	if (!cfg)
+		return;
+
+	/* Put both PLLs in bypass */
+	clk_write_bypass_mainpll(plat, CLKMGR_BYPASS_MAINPLL_ALL);
+	clk_write_bypass_perpll(plat, CLKMGR_BYPASS_PERPLL_ALL);
+
+	/* Put both PLLs in Reset and Power Down */
+	CM_REG_CLRBITS(plat, CLKMGR_MAINPLL_PLLGLOB,
+		       CLKMGR_PLLGLOB_PD_MASK | CLKMGR_PLLGLOB_RST_MASK);
+	CM_REG_CLRBITS(plat, CLKMGR_PERPLL_PLLGLOB,
+		       CLKMGR_PLLGLOB_PD_MASK | CLKMGR_PLLGLOB_RST_MASK);
+
+	/* setup main PLL dividers where calculate the vcocalib value */
+	vcocalib = calc_vocalib_pll(cfg->main_pll_pllm, cfg->main_pll_pllglob);
+	CM_REG_WRITEL(plat, cfg->main_pll_pllglob & ~CLKMGR_PLLGLOB_RST_MASK,
+		      CLKMGR_MAINPLL_PLLGLOB);
+	CM_REG_WRITEL(plat, cfg->main_pll_fdbck, CLKMGR_MAINPLL_FDBCK);
+	CM_REG_WRITEL(plat, vcocalib, CLKMGR_MAINPLL_VCOCALIB);
+	CM_REG_WRITEL(plat, cfg->main_pll_pllc0, CLKMGR_MAINPLL_PLLC0);
+	CM_REG_WRITEL(plat, cfg->main_pll_pllc1, CLKMGR_MAINPLL_PLLC1);
+	CM_REG_WRITEL(plat, cfg->main_pll_pllc2, CLKMGR_MAINPLL_PLLC2);
+	CM_REG_WRITEL(plat, cfg->main_pll_pllc3, CLKMGR_MAINPLL_PLLC3);
+	CM_REG_WRITEL(plat, cfg->main_pll_pllm, CLKMGR_MAINPLL_PLLM);
+	CM_REG_WRITEL(plat, cfg->main_pll_mpuclk, CLKMGR_MAINPLL_MPUCLK);
+	CM_REG_WRITEL(plat, cfg->main_pll_nocclk, CLKMGR_MAINPLL_NOCCLK);
+	CM_REG_WRITEL(plat, cfg->main_pll_nocdiv, CLKMGR_MAINPLL_NOCDIV);
+
+	/* setup peripheral PLL dividers where calculate the vcocalib value */
+	vcocalib = calc_vocalib_pll(cfg->per_pll_pllm, cfg->per_pll_pllglob);
+	CM_REG_WRITEL(plat, cfg->per_pll_pllglob & ~CLKMGR_PLLGLOB_RST_MASK,
+		      CLKMGR_PERPLL_PLLGLOB);
+	CM_REG_WRITEL(plat, cfg->per_pll_fdbck, CLKMGR_PERPLL_FDBCK);
+	CM_REG_WRITEL(plat, vcocalib, CLKMGR_PERPLL_VCOCALIB);
+	CM_REG_WRITEL(plat, cfg->per_pll_pllc0, CLKMGR_PERPLL_PLLC0);
+	CM_REG_WRITEL(plat, cfg->per_pll_pllc1, CLKMGR_PERPLL_PLLC1);
+	CM_REG_WRITEL(plat, cfg->per_pll_pllc2, CLKMGR_PERPLL_PLLC2);
+	CM_REG_WRITEL(plat, cfg->per_pll_pllc3, CLKMGR_PERPLL_PLLC3);
+	CM_REG_WRITEL(plat, cfg->per_pll_pllm, CLKMGR_PERPLL_PLLM);
+	CM_REG_WRITEL(plat, cfg->per_pll_emacctl, CLKMGR_PERPLL_EMACCTL);
+	CM_REG_WRITEL(plat, cfg->per_pll_gpiodiv, CLKMGR_PERPLL_GPIODIV);
+
+	/* Take both PLL out of reset and power up */
+	CM_REG_SETBITS(plat, CLKMGR_MAINPLL_PLLGLOB,
+		       CLKMGR_PLLGLOB_PD_MASK | CLKMGR_PLLGLOB_RST_MASK);
+	CM_REG_SETBITS(plat, CLKMGR_PERPLL_PLLGLOB,
+		       CLKMGR_PLLGLOB_PD_MASK | CLKMGR_PLLGLOB_RST_MASK);
+
+	/* Membus programming to set mainpll and perripll to
+	 * source synchronous mode
+	 */
+	membus_read_pll(plat, MEMBUS_MAINPLL, MEMBUS_ADDR_CLKSLICE, &rdata,
+			MEMBUS_TIMEOUT);
+	membus_write_pll(plat, MEMBUS_MAINPLL, MEMBUS_ADDR_CLKSLICE,
+			 (rdata | MEMBUS_CLKSLICE_SYNC_MODE_EN),
+			 MEMBUS_TIMEOUT);
+	membus_read_pll(plat, MEMBUS_PERPLL, MEMBUS_ADDR_CLKSLICE, &rdata,
+			MEMBUS_TIMEOUT);
+	membus_write_pll(plat, MEMBUS_PERPLL, MEMBUS_ADDR_CLKSLICE,
+			 (rdata | MEMBUS_CLKSLICE_SYNC_MODE_EN),
+			 MEMBUS_TIMEOUT);
+
+	cm_wait_for_lock(CLKMGR_STAT_ALLPLL_LOCKED_MASK);
+
+	/* Configure ping pong counters in altera group */
+	CM_REG_WRITEL(plat, cfg->alt_emacactr, CLKMGR_ALTR_EMACACTR);
+	CM_REG_WRITEL(plat, cfg->alt_emacbctr, CLKMGR_ALTR_EMACBCTR);
+	CM_REG_WRITEL(plat, cfg->alt_emacptpctr, CLKMGR_ALTR_EMACPTPCTR);
+	CM_REG_WRITEL(plat, cfg->alt_gpiodbctr, CLKMGR_ALTR_GPIODBCTR);
+	CM_REG_WRITEL(plat, cfg->alt_sdmmcctr, CLKMGR_ALTR_SDMMCCTR);
+	CM_REG_WRITEL(plat, cfg->alt_s2fuser0ctr, CLKMGR_ALTR_S2FUSER0CTR);
+	CM_REG_WRITEL(plat, cfg->alt_s2fuser1ctr, CLKMGR_ALTR_S2FUSER1CTR);
+	CM_REG_WRITEL(plat, cfg->alt_psirefctr, CLKMGR_ALTR_PSIREFCTR);
+
+	CM_REG_WRITEL(plat, CLKMGR_LOSTLOCK_SET_MASK, CLKMGR_MAINPLL_LOSTLOCK);
+	CM_REG_WRITEL(plat, CLKMGR_LOSTLOCK_SET_MASK, CLKMGR_PERPLL_LOSTLOCK);
+
+	CM_REG_WRITEL(plat, CM_REG_READL(plat, CLKMGR_MAINPLL_PLLGLOB) |
+			CLKMGR_PLLGLOB_CLR_LOSTLOCK_BYPASS_MASK,
+			CLKMGR_MAINPLL_PLLGLOB);
+	CM_REG_WRITEL(plat, CM_REG_READL(plat, CLKMGR_PERPLL_PLLGLOB) |
+			CLKMGR_PLLGLOB_CLR_LOSTLOCK_BYPASS_MASK,
+			CLKMGR_PERPLL_PLLGLOB);
+
+	/* Take all PLLs out of bypass */
+	clk_write_bypass_mainpll(plat, 0);
+	clk_write_bypass_perpll(plat, 0);
+
+	/* Clear the loss of lock bits (write 1 to clear) */
+	CM_REG_CLRBITS(plat, CLKMGR_INTRCLR,
+		       CLKMGR_INTER_PERPLLLOST_MASK |
+		       CLKMGR_INTER_MAINPLLLOST_MASK);
+
+	/* Take all ping pong counters out of reset */
+	CM_REG_CLRBITS(plat, CLKMGR_ALTR_EXTCNTRST,
+		       CLKMGR_ALT_EXTCNTRST_ALLCNTRST);
+
+	/* Out of boot mode */
+	clk_write_ctrl(plat,
+		       CM_REG_READL(plat, CLKMGR_CTRL) & ~CLKMGR_CTRL_BOOTMODE);
+}
+
+static u64 clk_get_vco_clk_hz(struct socfpga_clk_platdata *plat,
+			      u32 pllglob_reg, u32 pllm_reg)
+{
+	 u64 fref, arefdiv, mdiv, reg, vco;
+
+	reg = CM_REG_READL(plat, pllglob_reg);
+
+	fref = (reg & CLKMGR_PLLGLOB_VCO_PSRC_MASK) >>
+		CLKMGR_PLLGLOB_VCO_PSRC_OFFSET;
+
+	switch (fref) {
+	case CLKMGR_VCO_PSRC_EOSC1:
+		fref = cm_get_osc_clk_hz();
+		break;
+	case CLKMGR_VCO_PSRC_INTOSC:
+		fref = cm_get_intosc_clk_hz();
+		break;
+	case CLKMGR_VCO_PSRC_F2S:
+		fref = cm_get_fpga_clk_hz();
+		break;
+	}
+
+	arefdiv = (reg & CLKMGR_PLLGLOB_AREFCLKDIV_MASK) >>
+		   CLKMGR_PLLGLOB_AREFCLKDIV_OFFSET;
+
+	mdiv = CM_REG_READL(plat, pllm_reg) & CLKMGR_PLLM_MDIV_MASK;
+
+	vco = fref / arefdiv;
+	vco = vco * mdiv;
+
+	return vco;
+}
+
+static u64 clk_get_main_vco_clk_hz(struct socfpga_clk_platdata *plat)
+{
+	return clk_get_vco_clk_hz(plat, CLKMGR_MAINPLL_PLLGLOB,
+				 CLKMGR_MAINPLL_PLLM);
+}
+
+static u64 clk_get_per_vco_clk_hz(struct socfpga_clk_platdata *plat)
+{
+	return clk_get_vco_clk_hz(plat, CLKMGR_PERPLL_PLLGLOB,
+				 CLKMGR_PERPLL_PLLM);
+}
+
+static u32 clk_get_5_1_clk_src(struct socfpga_clk_platdata *plat, u64 reg)
+{
+	u32 clksrc = CM_REG_READL(plat, reg);
+
+	return (clksrc & CLKMGR_CLKSRC_MASK) >> CLKMGR_CLKSRC_OFFSET;
+}
+
+static u64 clk_get_clksrc_hz(struct socfpga_clk_platdata *plat, u32 clksrc_reg,
+			     u32 main_reg, u32 per_reg)
+{
+	u64 clock;
+	u32 clklsrc = clk_get_5_1_clk_src(plat, clksrc_reg);
+
+	switch (clklsrc) {
+	case CLKMGR_CLKSRC_MAIN:
+		clock = clk_get_main_vco_clk_hz(plat);
+		clock /= (CM_REG_READL(plat, main_reg) &
+			  CLKMGR_CLKCNT_MSK);
+		break;
+
+	case CLKMGR_CLKSRC_PER:
+		clock = clk_get_per_vco_clk_hz(plat);
+		clock /= (CM_REG_READL(plat, per_reg) &
+			  CLKMGR_CLKCNT_MSK);
+		break;
+
+	case CLKMGR_CLKSRC_OSC1:
+		clock = cm_get_osc_clk_hz();
+		break;
+
+	case CLKMGR_CLKSRC_INTOSC:
+		clock = cm_get_intosc_clk_hz();
+		break;
+
+	case CLKMGR_CLKSRC_FPGA:
+		clock = cm_get_fpga_clk_hz();
+		break;
+	default:
+		return 0;
+	}
+
+	return clock;
+}
+
+static u64 clk_get_mpu_clk_hz(struct socfpga_clk_platdata *plat)
+{
+	u64 clock = clk_get_clksrc_hz(plat, CLKMGR_MAINPLL_MPUCLK,
+				      CLKMGR_MAINPLL_PLLC0,
+				      CLKMGR_PERPLL_PLLC0);
+
+	clock /= 1 + (CM_REG_READL(plat, CLKMGR_MAINPLL_MPUCLK) &
+		 CLKMGR_CLKCNT_MSK);
+
+	return clock;
+}
+
+static u32 clk_get_l3_main_clk_hz(struct socfpga_clk_platdata *plat)
+{
+	return clk_get_clksrc_hz(plat, CLKMGR_MAINPLL_NOCCLK,
+				      CLKMGR_MAINPLL_PLLC1,
+				      CLKMGR_PERPLL_PLLC1);
+}
+
+static u32 clk_get_l4_main_clk_hz(struct socfpga_clk_platdata *plat)
+{
+	u64 clock = clk_get_l3_main_clk_hz(plat);
+
+	clock /= BIT((CM_REG_READL(plat, CLKMGR_MAINPLL_NOCDIV) >>
+	      CLKMGR_NOCDIV_L4MAIN_OFFSET) &
+	      CLKMGR_NOCDIV_DIVIDER_MASK);
+
+	return clock;
+}
+
+static u32 clk_get_sdmmc_clk_hz(struct socfpga_clk_platdata *plat)
+{
+	u64 clock = clk_get_clksrc_hz(plat, CLKMGR_ALTR_SDMMCCTR,
+				      CLKMGR_MAINPLL_PLLC3,
+				      CLKMGR_PERPLL_PLLC3);
+
+	clock /= 1 + (CM_REG_READL(plat, CLKMGR_ALTR_SDMMCCTR) &
+		 CLKMGR_CLKCNT_MSK);
+
+	return clock / 4;
+}
+
+static u32 clk_get_l4_sp_clk_hz(struct socfpga_clk_platdata *plat)
+{
+	u64 clock = clk_get_l3_main_clk_hz(plat);
+
+	clock /= BIT((CM_REG_READL(plat, CLKMGR_MAINPLL_NOCDIV) >>
+		      CLKMGR_NOCDIV_L4SPCLK_OFFSET) &
+		      CLKMGR_NOCDIV_DIVIDER_MASK);
+
+	return clock;
+}
+
+static u32 clk_get_l4_mp_clk_hz(struct socfpga_clk_platdata *plat)
+{
+	u64 clock = clk_get_l3_main_clk_hz(plat);
+
+	clock /= BIT((CM_REG_READL(plat, CLKMGR_MAINPLL_NOCDIV) >>
+		      CLKMGR_NOCDIV_L4MPCLK_OFFSET) &
+		      CLKMGR_NOCDIV_DIVIDER_MASK);
+
+	return clock;
+}
+
+static u32 clk_get_l4_sys_free_clk_hz(struct socfpga_clk_platdata *plat)
+{
+	if (CM_REG_READL(plat, CLKMGR_STAT) & CLKMGR_STAT_BOOTMODE)
+		return clk_get_l3_main_clk_hz(plat) / 2;
+
+	return clk_get_l3_main_clk_hz(plat) / 4;
+}
+
+static u32 clk_get_emac_clk_hz(struct socfpga_clk_platdata *plat, u32 emac_id)
+{
+	bool emacsel_a;
+	u32 ctl;
+	u32 ctr_reg;
+	u32 clock;
+	u32 div;
+	u32 reg;
+
+	/* Get EMAC clock source */
+	ctl = CM_REG_READL(plat, CLKMGR_PERPLL_EMACCTL);
+	if (emac_id == AGILEX_EMAC0_CLK)
+		ctl = (ctl >> CLKMGR_PERPLLGRP_EMACCTL_EMAC0SELB_OFFSET) &
+		       CLKMGR_PERPLLGRP_EMACCTL_EMAC0SELB_MASK;
+	else if (emac_id == AGILEX_EMAC1_CLK)
+		ctl = (ctl >> CLKMGR_PERPLLGRP_EMACCTL_EMAC1SELB_OFFSET) &
+		       CLKMGR_PERPLLGRP_EMACCTL_EMAC1SELB_MASK;
+	else if (emac_id == AGILEX_EMAC2_CLK)
+		ctl = (ctl >> CLKMGR_PERPLLGRP_EMACCTL_EMAC2SELB_OFFSET) &
+		       CLKMGR_PERPLLGRP_EMACCTL_EMAC2SELB_MASK;
+	else
+		return 0;
+
+	if (ctl) {
+		/* EMAC B source */
+		emacsel_a = false;
+		ctr_reg = CLKMGR_ALTR_EMACBCTR;
+	} else {
+		/* EMAC A source */
+		emacsel_a = true;
+		ctr_reg = CLKMGR_ALTR_EMACACTR;
+	}
+
+	reg = CM_REG_READL(plat, ctr_reg);
+	clock = (reg & CLKMGR_ALT_EMACCTR_SRC_MASK)
+		 >> CLKMGR_ALT_EMACCTR_SRC_OFFSET;
+	div = (reg & CLKMGR_ALT_EMACCTR_CNT_MASK)
+		>> CLKMGR_ALT_EMACCTR_CNT_OFFSET;
+
+	switch (clock) {
+	case CLKMGR_CLKSRC_MAIN:
+		clock = clk_get_main_vco_clk_hz(plat);
+		if (emacsel_a) {
+			clock /= (CM_REG_READL(plat, CLKMGR_MAINPLL_PLLC2) &
+				  CLKMGR_CLKCNT_MSK);
+		} else {
+			clock /= (CM_REG_READL(plat, CLKMGR_MAINPLL_PLLC3) &
+				  CLKMGR_CLKCNT_MSK);
+		}
+		break;
+
+	case CLKMGR_CLKSRC_PER:
+		clock = clk_get_per_vco_clk_hz(plat);
+		if (emacsel_a) {
+			clock /= (CM_REG_READL(plat, CLKMGR_PERPLL_PLLC2) &
+				  CLKMGR_CLKCNT_MSK);
+		} else {
+			clock /= (CM_REG_READL(plat, CLKMGR_PERPLL_PLLC3) &
+				  CLKMGR_CLKCNT_MSK);
+		}
+		break;
+
+	case CLKMGR_CLKSRC_OSC1:
+		clock = cm_get_osc_clk_hz();
+		break;
+
+	case CLKMGR_CLKSRC_INTOSC:
+		clock = cm_get_intosc_clk_hz();
+		break;
+
+	case CLKMGR_CLKSRC_FPGA:
+		clock = cm_get_fpga_clk_hz();
+		break;
+	}
+
+	clock /= 1 + div;
+
+	return clock;
+}
+
+static ulong socfpga_clk_get_rate(struct clk *clk)
+{
+	struct socfpga_clk_platdata *plat = dev_get_platdata(clk->dev);
+
+	switch (clk->id) {
+	case AGILEX_MPU_CLK:
+		return clk_get_mpu_clk_hz(plat);
+	case AGILEX_L4_MAIN_CLK:
+		return clk_get_l4_main_clk_hz(plat);
+	case AGILEX_L4_SYS_FREE_CLK:
+		return clk_get_l4_sys_free_clk_hz(plat);
+	case AGILEX_L4_MP_CLK:
+		return clk_get_l4_mp_clk_hz(plat);
+	case AGILEX_L4_SP_CLK:
+		return clk_get_l4_sp_clk_hz(plat);
+	case AGILEX_SDMMC_CLK:
+		return clk_get_sdmmc_clk_hz(plat);
+	case AGILEX_EMAC0_CLK:
+	case AGILEX_EMAC1_CLK:
+	case AGILEX_EMAC2_CLK:
+		return clk_get_emac_clk_hz(plat, clk->id);
+	case AGILEX_USB_CLK:
+		return clk_get_l4_mp_clk_hz(plat);
+	default:
+		return -ENXIO;
+	}
+}
+
+static int socfpga_clk_probe(struct udevice *dev)
+{
+	const struct cm_config *cm_default_cfg = cm_get_default_config();
+
+	clk_basic_init(dev, cm_default_cfg);
+
+	return 0;
+}
+
+static int socfpga_clk_ofdata_to_platdata(struct udevice *dev)
+{
+	struct socfpga_clk_platdata *plat = dev_get_platdata(dev);
+	fdt_addr_t addr;
+
+	addr = devfdt_get_addr(dev);
+	if (addr == FDT_ADDR_T_NONE)
+		return -EINVAL;
+	plat->regs = (void __iomem *)addr;
+
+	return 0;
+}
+
+static struct clk_ops socfpga_clk_ops = {
+	.get_rate	= socfpga_clk_get_rate,
+};
+
+static const struct udevice_id socfpga_clk_match[] = {
+	{ .compatible = "intel,agilex-clkmgr" },
+	{}
+};
+
+U_BOOT_DRIVER(socfpga_agilex_clk) = {
+	.name		= "clk-agilex",
+	.id		= UCLASS_CLK,
+	.of_match	= socfpga_clk_match,
+	.ops		= &socfpga_clk_ops,
+	.probe		= socfpga_clk_probe,
+	.ofdata_to_platdata = socfpga_clk_ofdata_to_platdata,
+	.platdata_auto_alloc_size = sizeof(struct socfpga_clk_platdata),
+};