[U-Boot] [PATCH v6 09/19] clk: agilex: Add clock driver for Agilex

Ley Foon Tan ley.foon.tan at intel.com
Fri Nov 8 04:11:13 UTC 2019


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 at intel.com>
Signed-off-by: Ley Foon Tan <ley.foon.tan at intel.com>
Reviewed-by: Simon Goldschmidt <simon.k.r.goldschmidt at gmail.com>

---
v6:
- Use agilex-clock.h from Linux instead of using stratix10-clock.h.

v4:
- Get address from DT.

v3:
- Fixed clear PLL's lostlock bypass mode to ensure the clock manager provide glitchless clock
to downstream logic
- Changed CM_REG_CLRBITS(), CM_REG_SETBITS() and CM_REG_CLRSETBITS() macros
argument ordering, to match with clrbits_le32, setbits_le32 and clrsetbits_le32.
- Rename stratix10-clock.h to socfpga-soc64-clock.h.
- Convert struct to defines and move defines to clk-agilex.h

v2:
- Convert Clock driver to DM
---
 arch/arm/mach-socfpga/misc.c             |   5 +
 drivers/clk/altera/Makefile              |   1 +
 drivers/clk/altera/clk-agilex.c          | 579 +++++++++++++++++++++++
 drivers/clk/altera/clk-agilex.h          | 237 ++++++++++
 include/dt-bindings/clock/agilex-clock.h |  70 +++
 5 files changed, 892 insertions(+)
 create mode 100644 drivers/clk/altera/clk-agilex.c
 create mode 100644 drivers/clk/altera/clk-agilex.h
 create mode 100644 include/dt-bindings/clock/agilex-clock.h

diff --git a/arch/arm/mach-socfpga/misc.c b/arch/arm/mach-socfpga/misc.c
index 1c6a0032dd..c95d9f6f43 100644
--- a/arch/arm/mach-socfpga/misc.c
+++ b/arch/arm/mach-socfpga/misc.c
@@ -244,7 +244,12 @@ void socfpga_get_managers_addr(void)
 	if (ret)
 		hang();
 
+#ifdef CONFIG_TARGET_SOCFPGA_AGILEX
+	ret = socfpga_get_base_addr("intel,agilex-clkmgr",
+				    &socfpga_clkmgr_base);
+#else
 	ret = socfpga_get_base_addr("altr,clk-mgr", &socfpga_clkmgr_base);
+#endif
 	if (ret)
 		hang();
 }
diff --git a/drivers/clk/altera/Makefile b/drivers/clk/altera/Makefile
index a3ae8b24b0..96215ad5c4 100644
--- a/drivers/clk/altera/Makefile
+++ b/drivers/clk/altera/Makefile
@@ -3,4 +3,5 @@
 # Copyright (C) 2018 Marek Vasut <marex at denx.de>
 #
 
+obj-$(CONFIG_TARGET_SOCFPGA_AGILEX) += clk-agilex.o
 obj-$(CONFIG_TARGET_SOCFPGA_ARRIA10) += clk-arria10.o
diff --git a/drivers/clk/altera/clk-agilex.c b/drivers/clk/altera/clk-agilex.c
new file mode 100644
index 0000000000..5fedec549d
--- /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),
+};
diff --git a/drivers/clk/altera/clk-agilex.h b/drivers/clk/altera/clk-agilex.h
new file mode 100644
index 0000000000..d93328ef29
--- /dev/null
+++ b/drivers/clk/altera/clk-agilex.h
@@ -0,0 +1,237 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Intel Corporation <www.intel.com>
+ */
+
+#ifndef	_CLK_AGILEX_
+#define	_CLK_AGILEX_
+
+#define CM_REG_READL(plat, reg)				\
+	readl((plat)->regs + (reg))
+
+#define CM_REG_WRITEL(plat, data, reg)			\
+	writel(data, (plat)->regs + (reg))
+
+#define CM_REG_CLRBITS(plat, reg, clear)		\
+	clrbits_le32((plat)->regs + (reg), (clear))
+
+#define CM_REG_SETBITS(plat, reg, set)			\
+	setbits_le32((plat)->regs + (reg), (set))
+
+struct cm_config {
+	/* main group */
+	u32 main_pll_mpuclk;
+	u32 main_pll_nocclk;
+	u32 main_pll_nocdiv;
+	u32 main_pll_pllglob;
+	u32 main_pll_fdbck;
+	u32 main_pll_pllc0;
+	u32 main_pll_pllc1;
+	u32 main_pll_pllc2;
+	u32 main_pll_pllc3;
+	u32 main_pll_pllm;
+
+	/* peripheral group */
+	u32 per_pll_emacctl;
+	u32 per_pll_gpiodiv;
+	u32 per_pll_pllglob;
+	u32 per_pll_fdbck;
+	u32 per_pll_pllc0;
+	u32 per_pll_pllc1;
+	u32 per_pll_pllc2;
+	u32 per_pll_pllc3;
+	u32 per_pll_pllm;
+
+	/* altera group */
+	u32 alt_emacactr;
+	u32 alt_emacbctr;
+	u32 alt_emacptpctr;
+	u32 alt_gpiodbctr;
+	u32 alt_sdmmcctr;
+	u32 alt_s2fuser0ctr;
+	u32 alt_s2fuser1ctr;
+	u32 alt_psirefctr;
+
+	/* incoming clock */
+	u32 hps_osc_clk_hz;
+	u32 fpga_clk_hz;
+	u32 spare[3];
+};
+
+/* Clock Manager registers */
+#define CLKMGR_CTRL				0
+#define CLKMGR_STAT				4
+#define CLKMGR_TESTIOCTRL			8
+#define CLKMGR_INTRGEN				0x0c
+#define CLKMGR_INTRMSK				0x10
+#define CLKMGR_INTRCLR				0x14
+#define CLKMGR_INTRSTS				0x18
+#define CLKMGR_INTRSTK				0x1c
+#define CLKMGR_INTRRAW				0x20
+
+/* Clock Manager Main PPL group registers */
+#define CLKMGR_MAINPLL_EN			0x24
+#define CLKMGR_MAINPLL_ENS			0x28
+#define CLKMGR_MAINPLL_ENR			0x2c
+#define CLKMGR_MAINPLL_BYPASS			0x30
+#define CLKMGR_MAINPLL_BYPASSS			0x34
+#define CLKMGR_MAINPLL_BYPASSR			0x38
+#define CLKMGR_MAINPLL_MPUCLK			0x3c
+#define CLKMGR_MAINPLL_NOCCLK			0x40
+#define CLKMGR_MAINPLL_NOCDIV			0x44
+#define CLKMGR_MAINPLL_PLLGLOB			0x48
+#define CLKMGR_MAINPLL_FDBCK			0x4c
+#define CLKMGR_MAINPLL_MEM			0x50
+#define CLKMGR_MAINPLL_MEMSTAT			0x54
+#define CLKMGR_MAINPLL_PLLC0			0x58
+#define CLKMGR_MAINPLL_PLLC1			0x5c
+#define CLKMGR_MAINPLL_VCOCALIB			0x60
+#define CLKMGR_MAINPLL_PLLC2			0x64
+#define CLKMGR_MAINPLL_PLLC3			0x68
+#define CLKMGR_MAINPLL_PLLM			0x6c
+#define CLKMGR_MAINPLL_FHOP			0x70
+#define CLKMGR_MAINPLL_SSC			0x74
+#define CLKMGR_MAINPLL_LOSTLOCK			0x78
+
+/* Clock Manager Peripheral PPL group registers */
+#define CLKMGR_PERPLL_EN			0x7c
+#define CLKMGR_PERPLL_ENS			0x80
+#define CLKMGR_PERPLL_ENR			0x84
+#define CLKMGR_PERPLL_BYPASS			0x88
+#define CLKMGR_PERPLL_BYPASSS			0x8c
+#define CLKMGR_PERPLL_BYPASSR			0x90
+#define CLKMGR_PERPLL_EMACCTL			0x94
+#define CLKMGR_PERPLL_GPIODIV			0x98
+#define CLKMGR_PERPLL_PLLGLOB			0x9c
+#define CLKMGR_PERPLL_FDBCK			0xa0
+#define CLKMGR_PERPLL_MEM			0xa4
+#define CLKMGR_PERPLL_MEMSTAT			0xa8
+#define CLKMGR_PERPLL_PLLC0			0xac
+#define CLKMGR_PERPLL_PLLC1			0xb0
+#define CLKMGR_PERPLL_VCOCALIB			0xb4
+#define CLKMGR_PERPLL_PLLC2			0xb8
+#define CLKMGR_PERPLL_PLLC3			0xbc
+#define CLKMGR_PERPLL_PLLM			0xc0
+#define CLKMGR_PERPLL_FHOP			0xc4
+#define CLKMGR_PERPLL_SSC			0xc8
+#define CLKMGR_PERPLL_LOSTLOCK			0xcc
+
+/* Clock Manager Altera group registers */
+#define CLKMGR_ALTR_JTAG			0xd0
+#define CLKMGR_ALTR_EMACACTR			0xd4
+#define CLKMGR_ALTR_EMACBCTR			0xd8
+#define CLKMGR_ALTR_EMACPTPCTR			0xdc
+#define CLKMGR_ALTR_GPIODBCTR			0xe0
+#define CLKMGR_ALTR_SDMMCCTR			0xe4
+#define CLKMGR_ALTR_S2FUSER0CTR			0xe8
+#define CLKMGR_ALTR_S2FUSER1CTR			0xec
+#define CLKMGR_ALTR_PSIREFCTR			0xf0
+#define CLKMGR_ALTR_EXTCNTRST			0xf4
+
+#define CLKMGR_CTRL_BOOTMODE			BIT(0)
+
+#define CLKMGR_STAT_BUSY			BIT(0)
+#define CLKMGR_STAT_MAINPLL_LOCKED		BIT(8)
+#define CLKMGR_STAT_MAIN_TRANS			BIT(9)
+#define CLKMGR_STAT_PERPLL_LOCKED		BIT(16)
+#define CLKMGR_STAT_PERF_TRANS			BIT(17)
+#define CLKMGR_STAT_BOOTMODE			BIT(24)
+#define CLKMGR_STAT_BOOTCLKSRC			BIT(25)
+
+#define CLKMGR_STAT_ALLPLL_LOCKED_MASK		\
+	(CLKMGR_STAT_MAINPLL_LOCKED | CLKMGR_STAT_PERPLL_LOCKED)
+
+#define CLKMGR_INTER_MAINPLLLOCKED_MASK		0x00000001
+#define CLKMGR_INTER_PERPLLLOCKED_MASK		0x00000002
+#define CLKMGR_INTER_MAINPLLLOST_MASK		0x00000004
+#define CLKMGR_INTER_PERPLLLOST_MASK		0x00000008
+
+#define CLKMGR_CLKSRC_MASK			GENMASK(18, 16)
+#define CLKMGR_CLKSRC_OFFSET			16
+#define CLKMGR_CLKSRC_MAIN			0
+#define CLKMGR_CLKSRC_PER			1
+#define CLKMGR_CLKSRC_OSC1			2
+#define CLKMGR_CLKSRC_INTOSC			3
+#define CLKMGR_CLKSRC_FPGA			4
+#define CLKMGR_CLKCNT_MSK			GENMASK(10, 0)
+
+#define CLKMGR_BYPASS_MAINPLL_ALL		0x7
+#define CLKMGR_BYPASS_PERPLL_ALL		0x7f
+
+#define CLKMGR_NOCDIV_L4MAIN_OFFSET		0
+#define CLKMGR_NOCDIV_L4MPCLK_OFFSET		8
+#define CLKMGR_NOCDIV_L4SPCLK_OFFSET		16
+#define CLKMGR_NOCDIV_CSATCLK_OFFSET		24
+#define CLKMGR_NOCDIV_CSTRACECLK_OFFSET		26
+#define CLKMGR_NOCDIV_CSPDBGCLK_OFFSET		28
+#define CLKMGR_NOCDIV_DIVIDER_MASK		0x3
+
+#define CLKMGR_PLLGLOB_PD_MASK				BIT(0)
+#define CLKMGR_PLLGLOB_RST_MASK				BIT(1)
+#define CLKMGR_PLLGLOB_AREFCLKDIV_MASK			GENMASK(11, 8)
+#define CLKMGR_PLLGLOB_DREFCLKDIV_MASK			GENMASK(13, 12)
+#define CLKMGR_PLLGLOB_REFCLKDIV_MASK			GENMASK(13, 8)
+#define CLKMGR_PLLGLOB_MODCLKDIV_MASK			GENMASK(24, 27)
+#define CLKMGR_PLLGLOB_AREFCLKDIV_OFFSET		8
+#define CLKMGR_PLLGLOB_DREFCLKDIV_OFFSET		12
+#define CLKMGR_PLLGLOB_REFCLKDIV_OFFSET			8
+#define CLKMGR_PLLGLOB_MODCLKDIV_OFFSET			24
+#define CLKMGR_PLLGLOB_VCO_PSRC_MASK			GENMASK(17, 16)
+#define CLKMGR_PLLGLOB_VCO_PSRC_OFFSET			16
+#define CLKMGR_PLLGLOB_CLR_LOSTLOCK_BYPASS_MASK		BIT(29)
+
+#define CLKMGR_VCO_PSRC_EOSC1			0
+#define CLKMGR_VCO_PSRC_INTOSC			1
+#define CLKMGR_VCO_PSRC_F2S			2
+
+#define CLKMGR_MEM_REQ_SET_MSK			BIT(24)
+#define CLKMGR_MEM_WR_SET_MSK			BIT(25)
+#define CLKMGR_MEM_ERR_MSK			BIT(26)
+#define CLKMGR_MEM_WDAT_LSB_OFFSET		16
+#define CLKMGR_MEM_ADDR_MASK			GENMASK(15, 0)
+#define CLKMGR_MEM_ADDR_START			0x00004000
+
+#define CLKMGR_PLLCX_EN_SET_MSK			BIT(27)
+#define CLKMGR_PLLCX_MUTE_SET_MSK		BIT(28)
+
+#define CLKMGR_VCOCALIB_MSCNT_MASK		GENMASK(23, 16)
+#define CLKMGR_VCOCALIB_MSCNT_OFFSET		16
+#define CLKMGR_VCOCALIB_HSCNT_MASK		GENMASK(9, 0)
+#define CLKMGR_VCOCALIB_MSCNT_CONST		100
+#define CLKMGR_VCOCALIB_HSCNT_CONST		4
+
+#define CLKMGR_PLLM_MDIV_MASK			GENMASK(9, 0)
+
+#define CLKMGR_LOSTLOCK_SET_MASK		BIT(0)
+
+#define CLKMGR_PERPLLGRP_EN_SDMMCCLK_MASK		BIT(5)
+#define CLKMGR_PERPLLGRP_EMACCTL_EMAC0SELB_OFFSET	26
+#define CLKMGR_PERPLLGRP_EMACCTL_EMAC0SELB_MASK		BIT(26)
+#define CLKMGR_PERPLLGRP_EMACCTL_EMAC1SELB_OFFSET	27
+#define CLKMGR_PERPLLGRP_EMACCTL_EMAC1SELB_MASK		BIT(27)
+#define CLKMGR_PERPLLGRP_EMACCTL_EMAC2SELB_OFFSET	28
+#define CLKMGR_PERPLLGRP_EMACCTL_EMAC2SELB_MASK		BIT(28)
+
+#define CLKMGR_ALT_EMACCTR_SRC_OFFSET		16
+#define CLKMGR_ALT_EMACCTR_SRC_MASK		GENMASK(18, 16)
+#define CLKMGR_ALT_EMACCTR_CNT_OFFSET		0
+#define CLKMGR_ALT_EMACCTR_CNT_MASK		GENMASK(10, 0)
+
+#define CLKMGR_ALT_EXTCNTRST_EMACACNTRST	BIT(0)
+#define CLKMGR_ALT_EXTCNTRST_EMACBCNTRST	BIT(1)
+#define CLKMGR_ALT_EXTCNTRST_EMACPTPCNTRST	BIT(2)
+#define CLKMGR_ALT_EXTCNTRST_GPIODBCNTRST	BIT(3)
+#define CLKMGR_ALT_EXTCNTRST_SDMMCCNTRST	BIT(4)
+#define CLKMGR_ALT_EXTCNTRST_S2FUSER0CNTRST	BIT(5)
+#define CLKMGR_ALT_EXTCNTRST_S2FUSER1CNTRST	BIT(6)
+#define CLKMGR_ALT_EXTCNTRST_PSIREFCNTRST	BIT(7)
+#define CLKMGR_ALT_EXTCNTRST_ALLCNTRST		\
+	(CLKMGR_ALT_EXTCNTRST_EMACACNTRST |	\
+	 CLKMGR_ALT_EXTCNTRST_EMACBCNTRST |	\
+	 CLKMGR_ALT_EXTCNTRST_EMACPTPCNTRST |	\
+	 CLKMGR_ALT_EXTCNTRST_GPIODBCNTRST |	\
+	 CLKMGR_ALT_EXTCNTRST_SDMMCCNTRST |	\
+	 CLKMGR_ALT_EXTCNTRST_S2FUSER0CNTRST |	\
+	 CLKMGR_ALT_EXTCNTRST_S2FUSER1CNTRST |	\
+	 CLKMGR_ALT_EXTCNTRST_PSIREFCNTRST)
+#endif /* _CLK_AGILEX_ */
diff --git a/include/dt-bindings/clock/agilex-clock.h b/include/dt-bindings/clock/agilex-clock.h
new file mode 100644
index 0000000000..b21485073d
--- /dev/null
+++ b/include/dt-bindings/clock/agilex-clock.h
@@ -0,0 +1,70 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019, Intel Corporation
+ */
+
+#ifndef __AGILEX_CLOCK_H
+#define __AGILEX_CLOCK_H
+
+/* fixed rate clocks */
+#define AGILEX_OSC1			0
+#define AGILEX_CB_INTOSC_HS_DIV2_CLK	1
+#define AGILEX_CB_INTOSC_LS_CLK		2
+#define AGILEX_L4_SYS_FREE_CLK		3
+#define AGILEX_F2S_FREE_CLK		4
+
+/* PLL clocks */
+#define AGILEX_MAIN_PLL_CLK		5
+#define AGILEX_MAIN_PLL_C0_CLK		6
+#define AGILEX_MAIN_PLL_C1_CLK		7
+#define AGILEX_MAIN_PLL_C2_CLK		8
+#define AGILEX_MAIN_PLL_C3_CLK		9
+#define AGILEX_PERIPH_PLL_CLK		10
+#define AGILEX_PERIPH_PLL_C0_CLK	11
+#define AGILEX_PERIPH_PLL_C1_CLK	12
+#define AGILEX_PERIPH_PLL_C2_CLK	13
+#define AGILEX_PERIPH_PLL_C3_CLK	14
+#define AGILEX_MPU_FREE_CLK		15
+#define AGILEX_MPU_CCU_CLK		16
+#define AGILEX_BOOT_CLK			17
+
+/* fixed factor clocks */
+#define AGILEX_L3_MAIN_FREE_CLK		18
+#define AGILEX_NOC_FREE_CLK		19
+#define AGILEX_S2F_USR0_CLK		20
+#define AGILEX_NOC_CLK			21
+#define AGILEX_EMAC_A_FREE_CLK		22
+#define AGILEX_EMAC_B_FREE_CLK		23
+#define AGILEX_EMAC_PTP_FREE_CLK	24
+#define AGILEX_GPIO_DB_FREE_CLK		25
+#define AGILEX_SDMMC_FREE_CLK		26
+#define AGILEX_S2F_USER0_FREE_CLK	27
+#define AGILEX_S2F_USER1_FREE_CLK	28
+#define AGILEX_PSI_REF_FREE_CLK		29
+
+/* Gate clocks */
+#define AGILEX_MPU_CLK			30
+#define AGILEX_MPU_L2RAM_CLK		31
+#define AGILEX_MPU_PERIPH_CLK		32
+#define AGILEX_L4_MAIN_CLK		33
+#define AGILEX_L4_MP_CLK		34
+#define AGILEX_L4_SP_CLK		35
+#define AGILEX_CS_AT_CLK		36
+#define AGILEX_CS_TRACE_CLK		37
+#define AGILEX_CS_PDBG_CLK		38
+#define AGILEX_CS_TIMER_CLK		39
+#define AGILEX_S2F_USER0_CLK		40
+#define AGILEX_EMAC0_CLK		41
+#define AGILEX_EMAC1_CLK		43
+#define AGILEX_EMAC2_CLK		44
+#define AGILEX_EMAC_PTP_CLK		45
+#define AGILEX_GPIO_DB_CLK		46
+#define AGILEX_NAND_CLK			47
+#define AGILEX_PSI_REF_CLK		48
+#define AGILEX_S2F_USER1_CLK		49
+#define AGILEX_SDMMC_CLK		50
+#define AGILEX_SPI_M_CLK		51
+#define AGILEX_USB_CLK			52
+#define AGILEX_NUM_CLKS			53
+
+#endif	/* __AGILEX_CLOCK_H */
\ No newline at end of file
-- 
2.19.0



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