diff mbox series

[v2,4/4] clk: eyeq: add driver

Message ID 20240703-mbly-clk-v2-4-fe8c6199a579@bootlin.com (mailing list archive)
State Superseded, archived
Headers show
Series Add Mobileye EyeQ clock support | expand

Commit Message

Théo Lebrun July 3, 2024, 1:46 p.m. UTC
Add Mobileye EyeQ5, EyeQ6L and EyeQ6H clock controller driver. It is
both a platform driver and a hook onto of_clk_init() used for clocks
required early (GIC timer, UARTs).

For some compatible, it is both at the same time. eqc_init() initialises
early PLLs and stores clock array in a static linked list. It marks
other clocks as deferred. eqc_probe() retrieves the clock array and
adds all remaining clocks.

It exposes read-only PLLs derived from the main crystal on board. It
also exposes another type of clocks: divider clocks. They always have
even divisors and have one PLL as parent.

This driver also bears the responsability for optional reset and pinctrl
auxiliary devices. The match data attached to the devicetree node
compatible indicate if such devices should be created. They all get
passed a pointer to the start of the OLB region.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
---
 drivers/clk/Kconfig    |  12 +
 drivers/clk/Makefile   |   1 +
 drivers/clk/clk-eyeq.c | 789 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 802 insertions(+)

Comments

kernel test robot July 5, 2024, 1:50 a.m. UTC | #1
Hi Théo,

kernel test robot noticed the following build errors:

[auto build test ERROR on f2661062f16b2de5d7b6a5c42a9a5c96326b8454]

url:    https://github.com/intel-lab-lkp/linux/commits/Th-o-Lebrun/Revert-dt-bindings-clock-mobileye-eyeq5-clk-add-bindings/20240704-211515
base:   f2661062f16b2de5d7b6a5c42a9a5c96326b8454
patch link:    https://lore.kernel.org/r/20240703-mbly-clk-v2-4-fe8c6199a579%40bootlin.com
patch subject: [PATCH v2 4/4] clk: eyeq: add driver
config: hexagon-allyesconfig (https://download.01.org/0day-ci/archive/20240705/202407050921.S41aCBdD-lkp@intel.com/config)
compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project a0c6b8aef853eedaa0980f07c0a502a5a8a9740e)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240705/202407050921.S41aCBdD-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202407050921.S41aCBdD-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from drivers/clk/clk-eyeq.c:30:
   In file included from include/linux/io.h:14:
   In file included from arch/hexagon/include/asm/io.h:328:
   include/asm-generic/io.h:548:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     548 |         val = __raw_readb(PCI_IOBASE + addr);
         |                           ~~~~~~~~~~ ^
   include/asm-generic/io.h:561:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     561 |         val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
         |                                                         ~~~~~~~~~~ ^
   include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
      37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
         |                                                   ^
   In file included from drivers/clk/clk-eyeq.c:30:
   In file included from include/linux/io.h:14:
   In file included from arch/hexagon/include/asm/io.h:328:
   include/asm-generic/io.h:574:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     574 |         val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
         |                                                         ~~~~~~~~~~ ^
   include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
      35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
         |                                                   ^
   In file included from drivers/clk/clk-eyeq.c:30:
   In file included from include/linux/io.h:14:
   In file included from arch/hexagon/include/asm/io.h:328:
   include/asm-generic/io.h:585:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     585 |         __raw_writeb(value, PCI_IOBASE + addr);
         |                             ~~~~~~~~~~ ^
   include/asm-generic/io.h:595:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     595 |         __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
         |                                                       ~~~~~~~~~~ ^
   include/asm-generic/io.h:605:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     605 |         __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
         |                                                       ~~~~~~~~~~ ^
>> drivers/clk/clk-eyeq.c:264:9: error: call to undeclared function 'readq'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     264 |                 val = readq(priv->base + pll->reg64);
         |                       ^
   drivers/clk/clk-eyeq.c:724:9: error: call to undeclared function 'readq'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     724 |                 val = readq(base + pll->reg64);
         |                       ^
   6 warnings and 2 errors generated.


vim +/readq +264 drivers/clk/clk-eyeq.c

   249	
   250	static void eqc_probe_init_plls(struct device *dev, struct eqc_priv *priv)
   251	{
   252		const struct eqc_match_data *data = priv->data;
   253		unsigned long mult, div, acc;
   254		const struct eqc_pll *pll;
   255		struct clk_hw *hw;
   256		unsigned int i;
   257		u32 r0, r1;
   258		u64 val;
   259		int ret;
   260	
   261		for (i = 0; i < data->pll_count; i++) {
   262			pll = &data->plls[i];
   263	
 > 264			val = readq(priv->base + pll->reg64);
   265			r0 = val;
   266			r1 = val >> 32;
   267	
   268			ret = eqc_pll_parse_registers(r0, r1, &mult, &div, &acc);
   269			if (ret) {
   270				dev_warn(dev, "failed parsing state of %s\n", pll->name);
   271				priv->cells->hws[pll->index] = ERR_PTR(ret);
   272				continue;
   273			}
   274	
   275			hw = clk_hw_register_fixed_factor_with_accuracy_fwname(dev,
   276					dev->of_node, pll->name, "ref", 0, mult, div, acc);
   277			priv->cells->hws[pll->index] = hw;
   278			if (IS_ERR(hw))
   279				dev_warn(dev, "failed registering %s: %pe\n", pll->name, hw);
   280		}
   281	}
   282
Théo Lebrun July 5, 2024, 10:03 a.m. UTC | #2
Hello,

*Grasp*, I forgot addressing this topic.

On Fri Jul 5, 2024 at 3:50 AM CEST, kernel test robot wrote:
> kernel test robot noticed the following build errors:

[...]

> All errors (new ones prefixed by >>):
>
>    In file included from drivers/clk/clk-eyeq.c:30:
>    In file included from include/linux/io.h:14:
>    In file included from arch/hexagon/include/asm/io.h:328:
>    include/asm-generic/io.h:548:31: warning: performing pointer
>        arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>      548 |         val = __raw_readb(PCI_IOBASE + addr);
>          |                           ~~~~~~~~~~ ^
[...]

Ignoring all the warnings relative to <linux/io.h> as they appear on all
objects using this config, nothing specific to clk-eyeq.

> >> drivers/clk/clk-eyeq.c:264:9: error: call to undeclared function
> >>     'readq'; ISO C99 and later do not support implicit function
> >>     declarations [-Wimplicit-function-declaration]
>      264 |                 val = readq(priv->base + pll->reg64);
>          |                       ^

Options are:

 - #include <linux/io-64-nonatomic-lo-hi.h> or
            <linux/io-64-nonatomic-hi-lo.h> or

 - in Kconfig, add "depends on 64BIT # for readq()"

I'm leaning towards the Kconfig option. Build testing this driver on
32bit platforms makes no sense, this is a SoC clk platform driver used
on 64bit SoCs. Including a compat layer is a more complex solution.

I'll wait a bit before sending next revision.
You can ping if you want it straight away of course.

Thanks,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
kernel test robot July 5, 2024, 4:41 p.m. UTC | #3
Hi Théo,

kernel test robot noticed the following build errors:

[auto build test ERROR on f2661062f16b2de5d7b6a5c42a9a5c96326b8454]

url:    https://github.com/intel-lab-lkp/linux/commits/Th-o-Lebrun/Revert-dt-bindings-clock-mobileye-eyeq5-clk-add-bindings/20240704-211515
base:   f2661062f16b2de5d7b6a5c42a9a5c96326b8454
patch link:    https://lore.kernel.org/r/20240703-mbly-clk-v2-4-fe8c6199a579%40bootlin.com
patch subject: [PATCH v2 4/4] clk: eyeq: add driver
config: s390-randconfig-r132-20240705 (https://download.01.org/0day-ci/archive/20240706/202407060044.YQzDGVPu-lkp@intel.com/config)
compiler: s390-linux-gcc (GCC) 13.2.0
reproduce: (https://download.01.org/0day-ci/archive/20240706/202407060044.YQzDGVPu-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202407060044.YQzDGVPu-lkp@intel.com/

All error/warnings (new ones prefixed by >>):

   drivers/clk/clk-eyeq.c: In function 'eqc_init':
>> drivers/clk/clk-eyeq.c:679:62: warning: dereferencing 'void *' pointer
     679 |         early_data = of_match_node(eqc_early_match_table, np)->data;
         |                                                              ^~
>> drivers/clk/clk-eyeq.c:679:62: error: request for member 'data' in something not a structure or union
   drivers/clk/clk-eyeq.c: At top level:
>> drivers/clk/clk-eyeq.c:653:34: warning: 'eqc_early_match_table' defined but not used [-Wunused-const-variable=]
     653 | static const struct of_device_id eqc_early_match_table[] = {
         |                                  ^~~~~~~~~~~~~~~~~~~~~


vim +/data +679 drivers/clk/clk-eyeq.c

   652	
 > 653	static const struct of_device_id eqc_early_match_table[] = {
   654		{
   655			.compatible = "mobileye,eyeq5-olb",
   656			.data = &eqc_eyeq5_early_match_data,
   657		},
   658		{
   659			.compatible = "mobileye,eyeq6h-central-olb",
   660			.data = &eqc_eyeq6h_central_early_match_data,
   661		},
   662		{
   663			.compatible = "mobileye,eyeq6h-west-olb",
   664			.data = &eqc_eyeq6h_west_early_match_data,
   665		},
   666		{}
   667	};
   668	MODULE_DEVICE_TABLE(of, eqc_early_match_table);
   669	
   670	static void __init eqc_init(struct device_node *np)
   671	{
   672		const struct eqc_early_match_data *early_data;
   673		unsigned int nb_clks = 0;
   674		struct eqc_priv *priv;
   675		void __iomem *base;
   676		unsigned int i;
   677		int ret;
   678	
 > 679		early_data = of_match_node(eqc_early_match_table, np)->data;
   680	
   681		/* No reason to early init this clock provider. Delay until probe. */
   682		if (!early_data || early_data->early_pll_count == 0)
   683			return;
   684	
   685		priv = kzalloc(sizeof(*priv), GFP_KERNEL);
   686		if (!priv) {
   687			ret = -ENOMEM;
   688			goto err;
   689		}
   690	
   691		priv->np = np;
   692		priv->early_data = early_data;
   693	
   694		nb_clks = early_data->early_pll_count + early_data->nb_late_clks;
   695		priv->cells = kzalloc(struct_size(priv->cells, hws, nb_clks), GFP_KERNEL);
   696		if (!priv->cells) {
   697			ret = -ENOMEM;
   698			goto err;
   699		}
   700	
   701		priv->cells->num = nb_clks;
   702	
   703		/*
   704		 * Mark all clocks as deferred; some are registered here, the rest at
   705		 * platform device probe.
   706		 */
   707		for (i = 0; i < nb_clks; i++)
   708			priv->cells->hws[i] = ERR_PTR(-EPROBE_DEFER);
   709	
   710		/* Offsets (reg64) of early PLLs are relative to OLB block. */
   711		base = of_iomap(np, 0);
   712		if (!base) {
   713			ret = -ENODEV;
   714			goto err;
   715		}
   716	
   717		for (i = 0; i < early_data->early_pll_count; i++) {
   718			const struct eqc_pll *pll = &early_data->early_plls[i];
   719			unsigned long mult, div, acc;
   720			struct clk_hw *hw;
   721			u32 r0, r1;
   722			u64 val;
   723	
   724			val = readq(base + pll->reg64);
   725			r0 = val;
   726			r1 = val >> 32;
   727	
   728			ret = eqc_pll_parse_registers(r0, r1, &mult, &div, &acc);
   729			if (ret) {
   730				pr_err("failed parsing state of %s\n", pll->name);
   731				goto err;
   732			}
   733	
   734			hw = clk_hw_register_fixed_factor_with_accuracy_fwname(NULL,
   735					np, pll->name, "ref", 0, mult, div, acc);
   736			priv->cells->hws[pll->index] = hw;
   737			if (IS_ERR(hw)) {
   738				pr_err("failed registering %s: %pe\n", pll->name, hw);
   739				ret = PTR_ERR(hw);
   740				goto err;
   741			}
   742		}
   743	
   744		/* When providing a single clock, require no cell. */
   745		if (nb_clks == 1)
   746			ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, priv->cells->hws[0]);
   747		else
   748			ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, priv->cells);
   749		if (ret) {
   750			pr_err("failed registering clk provider: %d\n", ret);
   751			goto err;
   752		}
   753	
   754		spin_lock(&eqc_list_slock);
   755		list_add_tail(&priv->list, &eqc_list);
   756		spin_unlock(&eqc_list_slock);
   757	
   758		return;
   759	
   760	err:
   761		/*
   762		 * We are doomed. The system will not be able to boot.
   763		 *
   764		 * Let's still try to be good citizens by freeing resources and print
   765		 * a last error message that might help debugging.
   766		 */
   767	
   768		if (priv && priv->cells) {
   769			of_clk_del_provider(np);
   770	
   771			for (i = 0; i < early_data->early_pll_count; i++) {
   772				const struct eqc_pll *pll = &early_data->early_plls[i];
   773				struct clk_hw *hw = priv->cells->hws[pll->index];
   774	
   775				if (!IS_ERR_OR_NULL(hw))
   776					clk_hw_unregister_fixed_factor(hw);
   777			}
   778	
   779			kfree(priv->cells);
   780		}
   781	
   782		kfree(priv);
   783	
   784		pr_err("failed clk init: %d\n", ret);
   785	}
   786
diff mbox series

Patch

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 3e9099504fad..271d55acac0a 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -218,6 +218,18 @@  config COMMON_CLK_EN7523
 	  This driver provides the fixed clocks and gates present on Airoha
 	  ARM silicon.
 
+config COMMON_CLK_EYEQ
+	bool "Clock driver for the Mobileye EyeQ platform"
+	depends on OF || COMPILE_TEST
+	depends on MACH_EYEQ5 || MACH_EYEQ6H || COMPILE_TEST
+	select AUXILIARY_BUS
+	default MACH_EYEQ5 || MACH_EYEQ6H
+	help
+	  This driver provides clocks found on Mobileye EyeQ5, EyeQ6L and Eye6H
+	  SoCs. Controllers live in shared register regions called OLB. Driver
+	  provides read-only PLLs, derived from the main crystal clock (which
+	  must be constant). It also exposes some divider clocks.
+
 config COMMON_CLK_FSL_FLEXSPI
 	tristate "Clock driver for FlexSPI on Layerscape SoCs"
 	depends on ARCH_LAYERSCAPE || COMPILE_TEST
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 4abe16c8ccdf..40bc2e48e1ab 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -32,6 +32,7 @@  obj-$(CONFIG_ARCH_CLPS711X)		+= clk-clps711x.o
 obj-$(CONFIG_COMMON_CLK_CS2000_CP)	+= clk-cs2000-cp.o
 obj-$(CONFIG_ARCH_SPARX5)		+= clk-sparx5.o
 obj-$(CONFIG_COMMON_CLK_EN7523)		+= clk-en7523.o
+obj-$(CONFIG_COMMON_CLK_EYEQ)		+= clk-eyeq.o
 obj-$(CONFIG_COMMON_CLK_FIXED_MMIO)	+= clk-fixed-mmio.o
 obj-$(CONFIG_COMMON_CLK_FSL_FLEXSPI)	+= clk-fsl-flexspi.o
 obj-$(CONFIG_COMMON_CLK_FSL_SAI)	+= clk-fsl-sai.o
diff --git a/drivers/clk/clk-eyeq.c b/drivers/clk/clk-eyeq.c
new file mode 100644
index 000000000000..8ce7f15e83c9
--- /dev/null
+++ b/drivers/clk/clk-eyeq.c
@@ -0,0 +1,789 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PLL clock driver for the Mobileye EyeQ5, EyeQ6L and EyeQ6H platforms.
+ *
+ * This controller handles read-only PLLs, all derived from the same main
+ * crystal clock. It also exposes divider clocks, those are children to PLLs.
+ * Parent clock is expected to be constant. This driver's registers live in
+ * a shared region called OLB. Some PLLs are initialised early by of_clk_init().
+ *
+ * We use eqc_ as prefix, as-in "EyeQ Clock", but way shorter.
+ *
+ * Copyright (C) 2024 Mobileye Vision Technologies Ltd.
+ */
+
+/*
+ * Set pr_fmt() for printing from eqc_init().
+ * It is called at of_clk_init() stage (read: really early).
+ */
+#define pr_fmt(fmt) "clk-eyeq: " fmt
+
+#include <linux/array_size.h>
+#include <linux/auxiliary_bus.h>
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/overflow.h>
+#include <linux/platform_device.h>
+#include <linux/printk.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#include <dt-bindings/clock/mobileye,eyeq5-clk.h>
+
+#define EQC_MAX_DIV_COUNT		4
+
+/* In frac mode, it enables fractional noise canceling DAC. Else, no function. */
+#define PCSR0_DAC_EN			BIT(0)
+/* Fractional or integer mode */
+#define PCSR0_DSM_EN			BIT(1)
+#define PCSR0_PLL_EN			BIT(2)
+/* All clocks output held at 0 */
+#define PCSR0_FOUTPOSTDIV_EN		BIT(3)
+#define PCSR0_POST_DIV1			GENMASK(6, 4)
+#define PCSR0_POST_DIV2			GENMASK(9, 7)
+#define PCSR0_REF_DIV			GENMASK(15, 10)
+#define PCSR0_INTIN			GENMASK(27, 16)
+#define PCSR0_BYPASS			BIT(28)
+/* Bits 30..29 are reserved */
+#define PCSR0_PLL_LOCKED		BIT(31)
+
+#define PCSR1_RESET			BIT(0)
+#define PCSR1_SSGC_DIV			GENMASK(4, 1)
+/* Spread amplitude (% = 0.1 * SPREAD[4:0]) */
+#define PCSR1_SPREAD			GENMASK(9, 5)
+#define PCSR1_DIS_SSCG			BIT(10)
+/* Down-spread or center-spread */
+#define PCSR1_DOWN_SPREAD		BIT(11)
+#define PCSR1_FRAC_IN			GENMASK(31, 12)
+
+/*
+ * Driver might register clock provider from eqc_init() if PLLs are required
+ * early (before platform bus is ready). Store struct eqc_priv inside linked
+ * list to pass clock provider from eqc_init() to eqc_probe() and register
+ * remaining clocks from platform device probe.
+ *
+ * Clock provider is NOT created by eqc_init() if no early clock is required.
+ * Store as linked list because EyeQ6H has multiple clock controller instances.
+ * Matching is done based on devicetree node pointer.
+ */
+static DEFINE_SPINLOCK(eqc_list_slock);
+static LIST_HEAD(eqc_list);
+
+struct eqc_pll {
+	unsigned int	index;
+	const char	*name;
+	unsigned int	reg64;
+};
+
+/*
+ * Divider clock. Divider is 2*(v+1), with v the register value.
+ * Min divider is 2, max is 2*(2^width).
+ */
+struct eqc_div {
+	unsigned int	index;
+	const char	*name;
+	unsigned int	parent;
+	unsigned int	reg;
+	u8		shift;
+	u8		width;
+};
+
+struct eqc_match_data {
+	unsigned int		pll_count;
+	const struct eqc_pll	*plls;
+
+	unsigned int		div_count;
+	const struct eqc_div	*divs;
+
+	const char		*reset_auxdev_name;
+	const char		*pinctrl_auxdev_name;
+};
+
+struct eqc_early_match_data {
+	unsigned int		early_pll_count;
+	const struct eqc_pll	*early_plls;
+	/* Information required to init properly clk HW cells. */
+	unsigned int		nb_late_clks;
+};
+
+struct eqc_priv {
+	struct clk_hw_onecell_data	*cells;
+	const struct eqc_early_match_data *early_data;
+	const struct eqc_match_data	*data;
+	void __iomem			*base;
+	struct device_node		*np;
+	struct list_head		list;
+};
+
+/*
+ * Both factors (mult and div) must fit in 32 bits. When an operation overflows,
+ * this function throws away low bits so that factors still fit in 32 bits.
+ *
+ * Precision loss depends on amplitude of mult and div. Worst theorical
+ * loss is: (UINT_MAX+1) / UINT_MAX - 1 = 2.3e-10.
+ * This is 1Hz every 4.3GHz.
+ */
+static void eqc_pll_downshift_factors(unsigned long *mult, unsigned long *div)
+{
+	unsigned long biggest;
+	unsigned int shift;
+
+	/* This function can be removed if mult/div switch to unsigned long. */
+	static_assert(sizeof_field(struct clk_fixed_factor, mult) == sizeof(unsigned int));
+	static_assert(sizeof_field(struct clk_fixed_factor, div) == sizeof(unsigned int));
+
+	/* No overflow, nothing to be done. */
+	if (*mult <= UINT_MAX && *div <= UINT_MAX)
+		return;
+
+	/*
+	 * Compute the shift required to bring the biggest factor into unsigned
+	 * int range. That is, shift its highest set bit to the unsigned int
+	 * most significant bit.
+	 */
+	biggest = max(*mult, *div);
+	shift = __fls(biggest) - (BITS_PER_BYTE * sizeof(unsigned int)) + 1;
+
+	*mult >>= shift;
+	*div >>= shift;
+}
+
+static int eqc_pll_parse_registers(u32 r0, u32 r1, unsigned long *mult,
+				   unsigned long *div, unsigned long *acc)
+{
+	if (r0 & PCSR0_BYPASS) {
+		*mult = 1;
+		*div = 1;
+		*acc = 0;
+		return 0;
+	}
+
+	if (!(r0 & PCSR0_PLL_LOCKED))
+		return -EINVAL;
+
+	*mult = FIELD_GET(PCSR0_INTIN, r0);
+	*div = FIELD_GET(PCSR0_REF_DIV, r0);
+	if (r0 & PCSR0_FOUTPOSTDIV_EN)
+		*div *= FIELD_GET(PCSR0_POST_DIV1, r0) * FIELD_GET(PCSR0_POST_DIV2, r0);
+
+	/* Fractional mode, in 2^20 (0x100000) parts. */
+	if (r0 & PCSR0_DSM_EN) {
+		*div *= 0x100000;
+		*mult = *mult * 0x100000 + FIELD_GET(PCSR1_FRAC_IN, r1);
+	}
+
+	if (!*mult || !*div)
+		return -EINVAL;
+
+	/* Spread spectrum. */
+	if (!(r1 & (PCSR1_RESET | PCSR1_DIS_SSCG))) {
+		/*
+		 * Spread is 1/1000 parts of frequency, accuracy is half of
+		 * that. To get accuracy, convert to ppb (parts per billion).
+		 */
+		u32 spread = FIELD_GET(PCSR1_SPREAD, r1);
+
+		*acc = spread * 500000;
+		if (r1 & PCSR1_DOWN_SPREAD) {
+			/*
+			 * Downspreading: the central frequency is half a
+			 * spread lower.
+			 */
+			*mult *= 2000 - spread;
+			*div *= 2000;
+
+			/*
+			 * Previous operation might overflow 32 bits. If it
+			 * does, throw away the least amount of low bits.
+			 */
+			eqc_pll_downshift_factors(mult, div);
+		}
+	} else {
+		*acc = 0;
+	}
+
+	return 0;
+}
+
+static unsigned int eqc_compute_clock_count(const struct eqc_early_match_data *early_data,
+					    const struct eqc_match_data *data)
+{
+	unsigned int i, nb_clks = 0, sum = 0;
+
+	if (early_data) {
+		sum += early_data->early_pll_count;
+
+		for (i = 0; i < early_data->early_pll_count; i++)
+			if (early_data->early_plls[i].index >= nb_clks)
+				nb_clks = early_data->early_plls[i].index + 1;
+	}
+
+	if (data) {
+		sum += data->pll_count + data->div_count;
+
+		for (i = 0; i < data->pll_count; i++)
+			if (data->plls[i].index >= nb_clks)
+				nb_clks = data->plls[i].index + 1;
+
+		for (i = 0; i < data->div_count; i++)
+			if (data->divs[i].index >= nb_clks)
+				nb_clks = data->divs[i].index + 1;
+	}
+
+	/* We expect the biggest clock index to be 1 below the clock count. */
+	WARN_ON(nb_clks != sum);
+
+	return nb_clks;
+}
+
+static void eqc_probe_init_plls(struct device *dev, struct eqc_priv *priv)
+{
+	const struct eqc_match_data *data = priv->data;
+	unsigned long mult, div, acc;
+	const struct eqc_pll *pll;
+	struct clk_hw *hw;
+	unsigned int i;
+	u32 r0, r1;
+	u64 val;
+	int ret;
+
+	for (i = 0; i < data->pll_count; i++) {
+		pll = &data->plls[i];
+
+		val = readq(priv->base + pll->reg64);
+		r0 = val;
+		r1 = val >> 32;
+
+		ret = eqc_pll_parse_registers(r0, r1, &mult, &div, &acc);
+		if (ret) {
+			dev_warn(dev, "failed parsing state of %s\n", pll->name);
+			priv->cells->hws[pll->index] = ERR_PTR(ret);
+			continue;
+		}
+
+		hw = clk_hw_register_fixed_factor_with_accuracy_fwname(dev,
+				dev->of_node, pll->name, "ref", 0, mult, div, acc);
+		priv->cells->hws[pll->index] = hw;
+		if (IS_ERR(hw))
+			dev_warn(dev, "failed registering %s: %pe\n", pll->name, hw);
+	}
+}
+
+static void eqc_probe_init_divs(struct platform_device *pdev, struct device *dev,
+				struct eqc_priv *priv)
+{
+	const struct eqc_match_data *data = priv->data;
+	const struct eqc_div *div;
+	struct clk_hw *parent;
+	void __iomem *reg;
+	struct clk_hw *hw;
+	unsigned int i;
+
+	for (i = 0; i < data->div_count; i++) {
+		div = &data->divs[i];
+		reg = priv->base + div->reg;
+		parent = priv->cells->hws[div->parent];
+
+		hw = clk_hw_register_divider_table_parent_hw(dev, div->name,
+				parent, 0, reg, div->shift, div->width,
+				CLK_DIVIDER_EVEN_INTEGERS, NULL, NULL);
+		priv->cells->hws[div->index] = hw;
+		if (IS_ERR(hw))
+			dev_warn(dev, "failed registering %s: %pe\n",
+				 div->name, hw);
+	}
+}
+
+static void eqc_auxdev_release(struct device *dev)
+{
+	struct auxiliary_device *adev = to_auxiliary_dev(dev);
+
+	kfree(adev);
+}
+
+static void eqc_auxdev_unregister(void *arg)
+{
+	struct auxiliary_device *adev = arg;
+
+	auxiliary_device_delete(adev);
+	auxiliary_device_uninit(adev);
+}
+
+static int eqc_auxdev_create(struct device *dev, void __iomem *base,
+			     const char *name, u32 id)
+{
+	struct auxiliary_device *adev;
+	int ret;
+
+	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
+	if (!adev)
+		return -ENOMEM;
+
+	adev->name = name;
+	adev->dev.parent = dev;
+	adev->dev.platform_data = (void __force *)base;
+	adev->dev.release = eqc_auxdev_release;
+	adev->id = id;
+
+	ret = auxiliary_device_init(adev);
+	if (ret)
+		return ret;
+
+	ret = auxiliary_device_add(adev);
+	if (ret) {
+		auxiliary_device_uninit(adev);
+		return ret;
+	}
+
+	return devm_add_action_or_reset(dev, eqc_auxdev_unregister, adev);
+}
+
+static int eqc_probe(struct platform_device *pdev)
+{
+	const struct eqc_match_data *data;
+	struct device *dev = &pdev->dev;
+	struct eqc_priv *priv = NULL;
+	struct eqc_priv *entry;
+	unsigned int nb_clks;
+	void __iomem *base;
+	int ret;
+
+	data = device_get_match_data(dev);
+	if (!data)
+		return 0; /* No clocks nor auxdevs, we are done. */
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	/* Init optional reset auxiliary device. */
+	if (data->reset_auxdev_name) {
+		ret = eqc_auxdev_create(dev, base, data->reset_auxdev_name, 0);
+		if (ret)
+			dev_warn(dev, "failed creating auxiliary device %s.%s: %d\n",
+				 KBUILD_MODNAME, data->reset_auxdev_name, ret);
+	}
+
+	/* Init optional pinctrl auxiliary device. */
+	if (data->pinctrl_auxdev_name) {
+		ret = eqc_auxdev_create(dev, base, data->pinctrl_auxdev_name, 0);
+		if (ret)
+			dev_warn(dev, "failed creating auxiliary device %s.%s: %d\n",
+				 KBUILD_MODNAME, data->pinctrl_auxdev_name, ret);
+	}
+
+	if (data->pll_count + data->div_count == 0)
+		return 0; /* Zero clocks, we are done. */
+
+	/* Try retrieving early init private data. */
+	spin_lock(&eqc_list_slock);
+	list_for_each_entry(entry, &eqc_list, list) {
+		if (entry->np == dev->of_node) {
+			priv = entry;
+			break;
+		}
+	}
+	spin_unlock(&eqc_list_slock);
+
+	if (!priv) {
+		/* Device did not get init early. Do it now. */
+
+		priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+		if (!priv)
+			return -ENOMEM;
+
+		priv->np = dev->of_node;
+
+		nb_clks = eqc_compute_clock_count(NULL, data);
+		priv->cells = devm_kzalloc(dev, struct_size(priv->cells, hws, nb_clks),
+					   GFP_KERNEL);
+		if (!priv->cells)
+			return -ENOMEM;
+
+		priv->cells->num = nb_clks;
+	} else {
+		/*
+		 * Device got init early. Check clock count.
+		 *
+		 * eqc_init() should already know the exact clk count using
+		 * nb_late_clks field. We ensure computation was right and fix
+		 * clk cells if not.
+		 */
+		nb_clks = eqc_compute_clock_count(priv->early_data, data);
+		if (WARN_ON(nb_clks != priv->cells->num))
+			priv->cells->num = nb_clks;
+	}
+
+	priv->base = base;
+	priv->data = data;
+
+	eqc_probe_init_plls(dev, priv);
+
+	eqc_probe_init_divs(pdev, dev, priv);
+
+	/* Clock provider has not been registered by eqc_init(). Do it now. */
+	if (!priv->early_data) {
+		/* When providing a single clock, require no cell. */
+		if (priv->cells->num == 1)
+			ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
+							  priv->cells->hws[0]);
+		else
+			ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
+							  priv->cells);
+
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static const struct eqc_pll eqc_eyeq5_plls[] = {
+	{ .index = EQ5C_PLL_VMP,  .name = "pll-vmp",  .reg64 = 0x034 },
+	{ .index = EQ5C_PLL_PMA,  .name = "pll-pma",  .reg64 = 0x03C },
+	{ .index = EQ5C_PLL_VDI,  .name = "pll-vdi",  .reg64 = 0x044 },
+	{ .index = EQ5C_PLL_DDR0, .name = "pll-ddr0", .reg64 = 0x04C },
+	{ .index = EQ5C_PLL_PCI,  .name = "pll-pci",  .reg64 = 0x054 },
+	{ .index = EQ5C_PLL_PMAC, .name = "pll-pmac", .reg64 = 0x064 },
+	{ .index = EQ5C_PLL_MPC,  .name = "pll-mpc",  .reg64 = 0x06C },
+	{ .index = EQ5C_PLL_DDR1, .name = "pll-ddr1", .reg64 = 0x074 },
+};
+
+static const struct eqc_div eqc_eyeq5_divs[] = {
+	{
+		.index = EQ5C_DIV_OSPI,
+		.name = "div-ospi",
+		.parent = EQ5C_PLL_PER,
+		.reg = 0x11C,
+		.shift = 0,
+		.width = 4,
+	},
+};
+
+static const struct eqc_match_data eqc_eyeq5_match_data = {
+	.pll_count	= ARRAY_SIZE(eqc_eyeq5_plls),
+	.plls		= eqc_eyeq5_plls,
+
+	.div_count	= ARRAY_SIZE(eqc_eyeq5_divs),
+	.divs		= eqc_eyeq5_divs,
+
+	.reset_auxdev_name = "reset",
+	.pinctrl_auxdev_name = "pinctrl",
+};
+
+static const struct eqc_pll eqc_eyeq6l_plls[] = {
+	{ .index = EQ6LC_PLL_DDR, .name = "pll-ddr", .reg64 = 0x02C },
+	{ .index = EQ6LC_PLL_CPU, .name = "pll-cpu", .reg64 = 0x034 }, /* also acc */
+	{ .index = EQ6LC_PLL_PER, .name = "pll-per", .reg64 = 0x03C },
+	{ .index = EQ6LC_PLL_VDI, .name = "pll-vdi", .reg64 = 0x044 },
+};
+
+static const struct eqc_match_data eqc_eyeq6l_match_data = {
+	.pll_count	= ARRAY_SIZE(eqc_eyeq6l_plls),
+	.plls		= eqc_eyeq6l_plls,
+
+	.reset_auxdev_name = "reset",
+};
+
+static const struct eqc_match_data eqc_eyeq6h_west_match_data = {
+	.reset_auxdev_name = "reset_west",
+};
+
+static const struct eqc_pll eqc_eyeq6h_east_plls[] = {
+	{ .index = 0, .name = "pll-east", .reg64 = 0x074 },
+};
+
+static const struct eqc_match_data eqc_eyeq6h_east_match_data = {
+	.pll_count	= ARRAY_SIZE(eqc_eyeq6h_east_plls),
+	.plls		= eqc_eyeq6h_east_plls,
+
+	.reset_auxdev_name = "reset_east",
+};
+
+static const struct eqc_pll eqc_eyeq6h_south_plls[] = {
+	{ .index = EQ6HC_SOUTH_PLL_VDI,  .name = "pll-vdi",  .reg64 = 0x000 },
+	{ .index = EQ6HC_SOUTH_PLL_PCIE, .name = "pll-pcie", .reg64 = 0x008 },
+	{ .index = EQ6HC_SOUTH_PLL_PER,  .name = "pll-per",  .reg64 = 0x010 },
+	{ .index = EQ6HC_SOUTH_PLL_ISP,  .name = "pll-isp",  .reg64 = 0x018 },
+};
+
+static const struct eqc_div eqc_eyeq6h_south_divs[] = {
+	{
+		.index = EQ6HC_SOUTH_DIV_EMMC,
+		.name = "div-emmc",
+		.parent = EQ6HC_SOUTH_PLL_PER,
+		.reg = 0x070,
+		.shift = 4,
+		.width = 4,
+	},
+	{
+		.index = EQ6HC_SOUTH_DIV_OSPI_REF,
+		.name = "div-ospi-ref",
+		.parent = EQ6HC_SOUTH_PLL_PER,
+		.reg = 0x090,
+		.shift = 4,
+		.width = 4,
+	},
+	{
+		.index = EQ6HC_SOUTH_DIV_OSPI_SYS,
+		.name = "div-ospi-sys",
+		.parent = EQ6HC_SOUTH_PLL_PER,
+		.reg = 0x090,
+		.shift = 8,
+		.width = 1,
+	},
+	{
+		.index = EQ6HC_SOUTH_DIV_TSU,
+		.name = "div-tsu",
+		.parent = EQ6HC_SOUTH_PLL_PCIE,
+		.reg = 0x098,
+		.shift = 4,
+		.width = 8,
+	},
+};
+
+static const struct eqc_match_data eqc_eyeq6h_south_match_data = {
+	.pll_count	= ARRAY_SIZE(eqc_eyeq6h_south_plls),
+	.plls		= eqc_eyeq6h_south_plls,
+
+	.div_count	= ARRAY_SIZE(eqc_eyeq6h_south_divs),
+	.divs		= eqc_eyeq6h_south_divs,
+};
+
+static const struct eqc_pll eqc_eyeq6h_ddr0_plls[] = {
+	{ .index = 0, .name = "pll-ddr0", .reg64 = 0x074 },
+};
+
+static const struct eqc_match_data eqc_eyeq6h_ddr0_match_data = {
+	.pll_count	= ARRAY_SIZE(eqc_eyeq6h_ddr0_plls),
+	.plls		= eqc_eyeq6h_ddr0_plls,
+};
+
+static const struct eqc_pll eqc_eyeq6h_ddr1_plls[] = {
+	{ .index = 0, .name = "pll-ddr1", .reg64 = 0x074 },
+};
+
+static const struct eqc_match_data eqc_eyeq6h_ddr1_match_data = {
+	.pll_count	= ARRAY_SIZE(eqc_eyeq6h_ddr1_plls),
+	.plls		= eqc_eyeq6h_ddr1_plls,
+};
+
+static const struct eqc_pll eqc_eyeq6h_acc_plls[] = {
+	{ .index = EQ6HC_ACC_PLL_XNN, .name = "pll-xnn", .reg64 = 0x040 },
+	{ .index = EQ6HC_ACC_PLL_VMP, .name = "pll-vmp", .reg64 = 0x050 },
+	{ .index = EQ6HC_ACC_PLL_PMA, .name = "pll-pma", .reg64 = 0x05C },
+	{ .index = EQ6HC_ACC_PLL_MPC, .name = "pll-mpc", .reg64 = 0x068 },
+	{ .index = EQ6HC_ACC_PLL_NOC, .name = "pll-noc", .reg64 = 0x070 },
+};
+
+static const struct eqc_match_data eqc_eyeq6h_acc_match_data = {
+	.pll_count	= ARRAY_SIZE(eqc_eyeq6h_acc_plls),
+	.plls		= eqc_eyeq6h_acc_plls,
+
+	.reset_auxdev_name = "reset_acc",
+};
+
+static const struct of_device_id eqc_match_table[] = {
+	{ .compatible = "mobileye,eyeq5-olb", .data = &eqc_eyeq5_match_data },
+	{ .compatible = "mobileye,eyeq6l-olb", .data = &eqc_eyeq6l_match_data },
+	{ .compatible = "mobileye,eyeq6h-west-olb", .data = &eqc_eyeq6h_west_match_data },
+	{ .compatible = "mobileye,eyeq6h-east-olb", .data = &eqc_eyeq6h_east_match_data },
+	{ .compatible = "mobileye,eyeq6h-south-olb", .data = &eqc_eyeq6h_south_match_data },
+	{ .compatible = "mobileye,eyeq6h-ddr0-olb", .data = &eqc_eyeq6h_ddr0_match_data },
+	{ .compatible = "mobileye,eyeq6h-ddr1-olb", .data = &eqc_eyeq6h_ddr1_match_data },
+	{ .compatible = "mobileye,eyeq6h-acc-olb", .data = &eqc_eyeq6h_acc_match_data },
+	{}
+};
+MODULE_DEVICE_TABLE(of, eqc_match_table);
+
+static struct platform_driver eqc_driver = {
+	.probe = eqc_probe,
+	.driver = {
+		.name = "clk-eyeq",
+		.of_match_table = eqc_match_table,
+	},
+};
+builtin_platform_driver(eqc_driver);
+
+/* Required early for GIC timer (pll-cpu) and UARTs (pll-per). */
+static const struct eqc_pll eqc_eyeq5_early_plls[] = {
+	{ .index = EQ5C_PLL_CPU, .name = "pll-cpu",  .reg64 = 0x02C },
+	{ .index = EQ5C_PLL_PER, .name = "pll-per",  .reg64 = 0x05C },
+};
+
+static const struct eqc_early_match_data eqc_eyeq5_early_match_data = {
+	.early_pll_count	= ARRAY_SIZE(eqc_eyeq5_early_plls),
+	.early_plls		= eqc_eyeq5_early_plls,
+	.nb_late_clks = eqc_eyeq5_match_data.pll_count + eqc_eyeq5_match_data.div_count,
+};
+
+/* Required early for GIC timer. */
+static const struct eqc_pll eqc_eyeq6h_central_early_plls[] = {
+	{ .index = 0, .name = "pll-cpu", .reg64 = 0x02C },
+};
+
+static const struct eqc_early_match_data eqc_eyeq6h_central_early_match_data = {
+	.early_pll_count	= ARRAY_SIZE(eqc_eyeq6h_central_early_plls),
+	.early_plls		= eqc_eyeq6h_central_early_plls,
+	.nb_late_clks = 0,
+};
+
+/* Required early for UART. */
+static const struct eqc_pll eqc_eyeq6h_west_early_plls[] = {
+	{ .index = 0, .name = "pll-west", .reg64 = 0x074 },
+};
+
+static const struct eqc_early_match_data eqc_eyeq6h_west_early_match_data = {
+	.early_pll_count	= ARRAY_SIZE(eqc_eyeq6h_west_early_plls),
+	.early_plls		= eqc_eyeq6h_west_early_plls,
+	.nb_late_clks = 0,
+};
+
+static const struct of_device_id eqc_early_match_table[] = {
+	{
+		.compatible = "mobileye,eyeq5-olb",
+		.data = &eqc_eyeq5_early_match_data,
+	},
+	{
+		.compatible = "mobileye,eyeq6h-central-olb",
+		.data = &eqc_eyeq6h_central_early_match_data,
+	},
+	{
+		.compatible = "mobileye,eyeq6h-west-olb",
+		.data = &eqc_eyeq6h_west_early_match_data,
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, eqc_early_match_table);
+
+static void __init eqc_init(struct device_node *np)
+{
+	const struct eqc_early_match_data *early_data;
+	unsigned int nb_clks = 0;
+	struct eqc_priv *priv;
+	void __iomem *base;
+	unsigned int i;
+	int ret;
+
+	early_data = of_match_node(eqc_early_match_table, np)->data;
+
+	/* No reason to early init this clock provider. Delay until probe. */
+	if (!early_data || early_data->early_pll_count == 0)
+		return;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	priv->np = np;
+	priv->early_data = early_data;
+
+	nb_clks = early_data->early_pll_count + early_data->nb_late_clks;
+	priv->cells = kzalloc(struct_size(priv->cells, hws, nb_clks), GFP_KERNEL);
+	if (!priv->cells) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	priv->cells->num = nb_clks;
+
+	/*
+	 * Mark all clocks as deferred; some are registered here, the rest at
+	 * platform device probe.
+	 */
+	for (i = 0; i < nb_clks; i++)
+		priv->cells->hws[i] = ERR_PTR(-EPROBE_DEFER);
+
+	/* Offsets (reg64) of early PLLs are relative to OLB block. */
+	base = of_iomap(np, 0);
+	if (!base) {
+		ret = -ENODEV;
+		goto err;
+	}
+
+	for (i = 0; i < early_data->early_pll_count; i++) {
+		const struct eqc_pll *pll = &early_data->early_plls[i];
+		unsigned long mult, div, acc;
+		struct clk_hw *hw;
+		u32 r0, r1;
+		u64 val;
+
+		val = readq(base + pll->reg64);
+		r0 = val;
+		r1 = val >> 32;
+
+		ret = eqc_pll_parse_registers(r0, r1, &mult, &div, &acc);
+		if (ret) {
+			pr_err("failed parsing state of %s\n", pll->name);
+			goto err;
+		}
+
+		hw = clk_hw_register_fixed_factor_with_accuracy_fwname(NULL,
+				np, pll->name, "ref", 0, mult, div, acc);
+		priv->cells->hws[pll->index] = hw;
+		if (IS_ERR(hw)) {
+			pr_err("failed registering %s: %pe\n", pll->name, hw);
+			ret = PTR_ERR(hw);
+			goto err;
+		}
+	}
+
+	/* When providing a single clock, require no cell. */
+	if (nb_clks == 1)
+		ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, priv->cells->hws[0]);
+	else
+		ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, priv->cells);
+	if (ret) {
+		pr_err("failed registering clk provider: %d\n", ret);
+		goto err;
+	}
+
+	spin_lock(&eqc_list_slock);
+	list_add_tail(&priv->list, &eqc_list);
+	spin_unlock(&eqc_list_slock);
+
+	return;
+
+err:
+	/*
+	 * We are doomed. The system will not be able to boot.
+	 *
+	 * Let's still try to be good citizens by freeing resources and print
+	 * a last error message that might help debugging.
+	 */
+
+	if (priv && priv->cells) {
+		of_clk_del_provider(np);
+
+		for (i = 0; i < early_data->early_pll_count; i++) {
+			const struct eqc_pll *pll = &early_data->early_plls[i];
+			struct clk_hw *hw = priv->cells->hws[pll->index];
+
+			if (!IS_ERR_OR_NULL(hw))
+				clk_hw_unregister_fixed_factor(hw);
+		}
+
+		kfree(priv->cells);
+	}
+
+	kfree(priv);
+
+	pr_err("failed clk init: %d\n", ret);
+}
+
+CLK_OF_DECLARE_DRIVER(eqc_eyeq5, "mobileye,eyeq5-olb", eqc_init);
+CLK_OF_DECLARE_DRIVER(eqc_eyeq6h_central, "mobileye,eyeq6h-central-olb", eqc_init);
+CLK_OF_DECLARE_DRIVER(eqc_eyeq6h_west, "mobileye,eyeq6h-west-olb", eqc_init);