drivers/i2c/designware_i2c_pci.c - platform/external/u-boot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * (C) Copyright 2009
  * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
  * Copyright 2019 Google Inc
  */

 #include <common.h>
 #include <dm.h>
 #include <log.h>
 #include <spl.h>
 #include <acpi/acpigen.h>
 #include <acpi/acpi_device.h>
 #include <asm/lpss.h>
 #include <dm/acpi.h>
 #include <dm/device-internal.h>
 #include <dm/uclass-internal.h>
 #include "designware_i2c.h"

 enum {
 	VANILLA		= 0,	/* standard I2C with no tweaks */
 	INTEL_APL,		/* Apollo Lake I2C */
 };

 /* BayTrail HCNT/LCNT/SDA hold time */
 static struct dw_scl_sda_cfg byt_config = {
 	.ss_hcnt = 0x200,
 	.fs_hcnt = 0x55,
 	.ss_lcnt = 0x200,
 	.fs_lcnt = 0x99,
 	.sda_hold = 0x6,
 };

 /* Have a weak function for now - possibly should be a new uclass */
 __weak void lpss_reset_release(void *regs);

 static int designware_i2c_pci_ofdata_to_platdata(struct udevice *dev)
 {
 	struct dw_i2c *priv = dev_get_priv(dev);

 	if (spl_phase() < PHASE_SPL) {
 		u32 base;
 		int ret;

 		ret = dev_read_u32(dev, "early-regs", &base);
 		if (ret)
 			return log_msg_ret("early-regs", ret);

 		/* Set i2c base address */
 		dm_pci_write_config32(dev, PCI_BASE_ADDRESS_0, base);

 		/* Enable memory access and bus master */
 		dm_pci_write_config32(dev, PCI_COMMAND, PCI_COMMAND_MEMORY |
 				      PCI_COMMAND_MASTER);
 	}

 	if (spl_phase() < PHASE_BOARD_F) {
 		/* Handle early, fixed mapping into a different address space */
 		priv->regs = (struct i2c_regs *)dm_pci_read_bar32(dev, 0);
 	} else {
 		priv->regs = (struct i2c_regs *)
 			dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0, PCI_REGION_MEM);
 	}
 	if (!priv->regs)
 		return -EINVAL;

 	/* Save base address from PCI BAR */
 	if (IS_ENABLED(CONFIG_INTEL_BAYTRAIL))
 		/* Use BayTrail specific timing values */
 		priv->scl_sda_cfg = &byt_config;
 	if (dev_get_driver_data(dev) == INTEL_APL)
 		priv->has_spk_cnt = true;

 	return designware_i2c_ofdata_to_platdata(dev);
 }

 static int designware_i2c_pci_probe(struct udevice *dev)
 {
 	struct dw_i2c *priv = dev_get_priv(dev);

 	if (dev_get_driver_data(dev) == INTEL_APL) {
 		/* Ensure controller is in D0 state */
 		lpss_set_power_state(dev, STATE_D0);

 		lpss_reset_release(priv->regs);
 	}

 	return designware_i2c_probe(dev);
 }

 static int designware_i2c_pci_bind(struct udevice *dev)
 {
 	char name[20];

 	if (dev_of_valid(dev))
 		return 0;

 	/*
 	 * Create a unique device name for PCI type devices
 	 * ToDo:
 	 * Setting req_seq in the driver is probably not recommended.
 	 * But without a DT alias the number is not configured. And
 	 * using this driver is impossible for PCIe I2C devices.
 	 * This can be removed, once a better (correct) way for this
 	 * is found and implemented.
 	 *
 	 * TODO(sjg@chromium.org): Perhaps if uclasses had platdata this would
 	 * be possible. We cannot use static data in drivers since they may be
 	 * used in SPL or before relocation.
 	 */
 	dev->req_seq = uclass_find_next_free_req_seq(UCLASS_I2C);
 	sprintf(name, "i2c_designware#%u", dev->req_seq);
 	device_set_name(dev, name);

 	return 0;
 }

 /*
  * Write ACPI object to describe speed configuration.
  *
  * ACPI Object: Name ("xxxx", Package () { scl_lcnt, scl_hcnt, sda_hold }
  *
  * SSCN: I2C_SPEED_STANDARD
  * FMCN: I2C_SPEED_FAST
  * FPCN: I2C_SPEED_FAST_PLUS
  * HSCN: I2C_SPEED_HIGH
  */
 static void dw_i2c_acpi_write_speed_config(struct acpi_ctx *ctx,
 					   struct dw_i2c_speed_config *config)
 {
 	switch (config->speed_mode) {
 	case IC_SPEED_MODE_HIGH:
 		acpigen_write_name(ctx, "HSCN");
 		break;
 	case IC_SPEED_MODE_FAST_PLUS:
 		acpigen_write_name(ctx, "FPCN");
 		break;
 	case IC_SPEED_MODE_FAST:
 		acpigen_write_name(ctx, "FMCN");
 		break;
 	case IC_SPEED_MODE_STANDARD:
 	default:
 		acpigen_write_name(ctx, "SSCN");
 	}

 	/* Package () { scl_lcnt, scl_hcnt, sda_hold } */
 	acpigen_write_package(ctx, 3);
 	acpigen_write_word(ctx, config->scl_hcnt);
 	acpigen_write_word(ctx, config->scl_lcnt);
 	acpigen_write_dword(ctx, config->sda_hold);
 	acpigen_pop_len(ctx);
 }

 /*
  * Generate I2C timing information into the SSDT for the OS driver to consume,
  * optionally applying override values provided by the caller.
  */
 static int dw_i2c_acpi_fill_ssdt(const struct udevice *dev,
 				 struct acpi_ctx *ctx)
 {
 	struct dw_i2c_speed_config config;
 	char path[ACPI_PATH_MAX];
 	u32 speeds[4];
 	uint speed;
 	int size;
 	int ret;

 	/* If no device-tree node, ignore this since we assume it isn't used */
 	if (!dev_of_valid(dev))
 		return 0;

 	ret = acpi_device_path(dev, path, sizeof(path));
 	if (ret)
 		return log_msg_ret("path", ret);

 	size = dev_read_size(dev, "i2c,speeds");
 	if (size < 0)
 		return log_msg_ret("i2c,speeds", -EINVAL);

 	size /= sizeof(u32);
 	if (size > ARRAY_SIZE(speeds))
 		return log_msg_ret("array", -E2BIG);

 	ret = dev_read_u32_array(dev, "i2c,speeds", speeds, size);
 	if (ret)
 		return log_msg_ret("read", -E2BIG);

 	speed = dev_read_u32_default(dev, "clock-frequency", 100000);
 	acpigen_write_scope(ctx, path);
 	ret = dw_i2c_gen_speed_config(dev, speed, &config);
 	if (ret)
 		return log_msg_ret("config", ret);
 	dw_i2c_acpi_write_speed_config(ctx, &config);
 	acpigen_pop_len(ctx);

 	return 0;
 }

 struct acpi_ops dw_i2c_acpi_ops = {
 	.fill_ssdt	= dw_i2c_acpi_fill_ssdt,
 };

 static const struct udevice_id designware_i2c_pci_ids[] = {
 	{ .compatible = "snps,designware-i2c-pci" },
 	{ .compatible = "intel,apl-i2c", .data = INTEL_APL },
 	{ }
 };

 U_BOOT_DRIVER(i2c_designware_pci) = {
 	.name	= "i2c_designware_pci",
 	.id	= UCLASS_I2C,
 	.of_match = designware_i2c_pci_ids,
 	.bind	= designware_i2c_pci_bind,
 	.ofdata_to_platdata	= designware_i2c_pci_ofdata_to_platdata,
 	.probe	= designware_i2c_pci_probe,
 	.priv_auto_alloc_size = sizeof(struct dw_i2c),
 	.remove = designware_i2c_remove,
 	.flags = DM_FLAG_OS_PREPARE,
 	.ops	= &designware_i2c_ops,
 	ACPI_OPS_PTR(&dw_i2c_acpi_ops)
 };

 static struct pci_device_id designware_pci_supported[] = {
 	/* Intel BayTrail has 7 I2C controller located on the PCI bus */
 	{ PCI_VDEVICE(INTEL, 0x0f41) },
 	{ PCI_VDEVICE(INTEL, 0x0f42) },
 	{ PCI_VDEVICE(INTEL, 0x0f43) },
 	{ PCI_VDEVICE(INTEL, 0x0f44) },
 	{ PCI_VDEVICE(INTEL, 0x0f45) },
 	{ PCI_VDEVICE(INTEL, 0x0f46) },
 	{ PCI_VDEVICE(INTEL, 0x0f47) },
 	{ PCI_VDEVICE(INTEL, 0x5aac), .driver_data = INTEL_APL },
 	{ PCI_VDEVICE(INTEL, 0x5aae), .driver_data = INTEL_APL },
 	{ PCI_VDEVICE(INTEL, 0x5ab0), .driver_data = INTEL_APL },
 	{ PCI_VDEVICE(INTEL, 0x5ab2), .driver_data = INTEL_APL },
 	{ PCI_VDEVICE(INTEL, 0x5ab4), .driver_data = INTEL_APL },
 	{ PCI_VDEVICE(INTEL, 0x5ab6), .driver_data = INTEL_APL },
 	{},
 };

 U_BOOT_PCI_DEVICE(i2c_designware_pci, designware_pci_supported);
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* (C) Copyright 2009
	* Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
	* Copyright 2019 Google Inc
	*/

	#include <common.h>
	#include <dm.h>
	#include <log.h>
	#include <spl.h>
	#include <acpi/acpigen.h>
	#include <acpi/acpi_device.h>
	#include <asm/lpss.h>
	#include <dm/acpi.h>
	#include <dm/device-internal.h>
	#include <dm/uclass-internal.h>
	#include "designware_i2c.h"

	enum {
	VANILLA = 0, /* standard I2C with no tweaks */
	INTEL_APL, /* Apollo Lake I2C */
	};

	/* BayTrail HCNT/LCNT/SDA hold time */
	static struct dw_scl_sda_cfg byt_config = {
	.ss_hcnt = 0x200,
	.fs_hcnt = 0x55,
	.ss_lcnt = 0x200,
	.fs_lcnt = 0x99,
	.sda_hold = 0x6,
	};

	/* Have a weak function for now - possibly should be a new uclass */
	__weak void lpss_reset_release(void *regs);

	static int designware_i2c_pci_ofdata_to_platdata(struct udevice *dev)
	{
	struct dw_i2c *priv = dev_get_priv(dev);

	if (spl_phase() < PHASE_SPL) {
	u32 base;
	int ret;

	ret = dev_read_u32(dev, "early-regs", &base);
	if (ret)
	return log_msg_ret("early-regs", ret);

	/* Set i2c base address */
	dm_pci_write_config32(dev, PCI_BASE_ADDRESS_0, base);

	/* Enable memory access and bus master */
	dm_pci_write_config32(dev, PCI_COMMAND, PCI_COMMAND_MEMORY \|
	PCI_COMMAND_MASTER);
	}

	if (spl_phase() < PHASE_BOARD_F) {
	/* Handle early, fixed mapping into a different address space */
	priv->regs = (struct i2c_regs *)dm_pci_read_bar32(dev, 0);
	} else {
	priv->regs = (struct i2c_regs *)
	dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0, PCI_REGION_MEM);
	}
	if (!priv->regs)
	return -EINVAL;

	/* Save base address from PCI BAR */
	if (IS_ENABLED(CONFIG_INTEL_BAYTRAIL))
	/* Use BayTrail specific timing values */
	priv->scl_sda_cfg = &byt_config;
	if (dev_get_driver_data(dev) == INTEL_APL)
	priv->has_spk_cnt = true;

	return designware_i2c_ofdata_to_platdata(dev);
	}

	static int designware_i2c_pci_probe(struct udevice *dev)
	{
	struct dw_i2c *priv = dev_get_priv(dev);

	if (dev_get_driver_data(dev) == INTEL_APL) {
	/* Ensure controller is in D0 state */
	lpss_set_power_state(dev, STATE_D0);

	lpss_reset_release(priv->regs);
	}

	return designware_i2c_probe(dev);
	}

	static int designware_i2c_pci_bind(struct udevice *dev)
	{
	char name[20];

	if (dev_of_valid(dev))
	return 0;

	/*
	* Create a unique device name for PCI type devices
	* ToDo:
	* Setting req_seq in the driver is probably not recommended.
	* But without a DT alias the number is not configured. And
	* using this driver is impossible for PCIe I2C devices.
	* This can be removed, once a better (correct) way for this
	* is found and implemented.
	*
	* TODO(sjg@chromium.org): Perhaps if uclasses had platdata this would
	* be possible. We cannot use static data in drivers since they may be
	* used in SPL or before relocation.
	*/
	dev->req_seq = uclass_find_next_free_req_seq(UCLASS_I2C);
	sprintf(name, "i2c_designware#%u", dev->req_seq);
	device_set_name(dev, name);

	return 0;
	}

	/*
	* Write ACPI object to describe speed configuration.
	*
	* ACPI Object: Name ("xxxx", Package () { scl_lcnt, scl_hcnt, sda_hold }
	*
	* SSCN: I2C_SPEED_STANDARD
	* FMCN: I2C_SPEED_FAST
	* FPCN: I2C_SPEED_FAST_PLUS
	* HSCN: I2C_SPEED_HIGH
	*/
	static void dw_i2c_acpi_write_speed_config(struct acpi_ctx *ctx,
	struct dw_i2c_speed_config *config)
	{
	switch (config->speed_mode) {
	case IC_SPEED_MODE_HIGH:
	acpigen_write_name(ctx, "HSCN");
	break;
	case IC_SPEED_MODE_FAST_PLUS:
	acpigen_write_name(ctx, "FPCN");
	break;
	case IC_SPEED_MODE_FAST:
	acpigen_write_name(ctx, "FMCN");
	break;
	case IC_SPEED_MODE_STANDARD:
	default:
	acpigen_write_name(ctx, "SSCN");
	}

	/* Package () { scl_lcnt, scl_hcnt, sda_hold } */
	acpigen_write_package(ctx, 3);
	acpigen_write_word(ctx, config->scl_hcnt);
	acpigen_write_word(ctx, config->scl_lcnt);
	acpigen_write_dword(ctx, config->sda_hold);
	acpigen_pop_len(ctx);
	}

	/*
	* Generate I2C timing information into the SSDT for the OS driver to consume,
	* optionally applying override values provided by the caller.
	*/
	static int dw_i2c_acpi_fill_ssdt(const struct udevice *dev,
	struct acpi_ctx *ctx)
	{
	struct dw_i2c_speed_config config;
	char path[ACPI_PATH_MAX];
	u32 speeds[4];
	uint speed;
	int size;
	int ret;

	/* If no device-tree node, ignore this since we assume it isn't used */
	if (!dev_of_valid(dev))
	return 0;

	ret = acpi_device_path(dev, path, sizeof(path));
	if (ret)
	return log_msg_ret("path", ret);

	size = dev_read_size(dev, "i2c,speeds");
	if (size < 0)
	return log_msg_ret("i2c,speeds", -EINVAL);

	size /= sizeof(u32);
	if (size > ARRAY_SIZE(speeds))
	return log_msg_ret("array", -E2BIG);

	ret = dev_read_u32_array(dev, "i2c,speeds", speeds, size);
	if (ret)
	return log_msg_ret("read", -E2BIG);

	speed = dev_read_u32_default(dev, "clock-frequency", 100000);
	acpigen_write_scope(ctx, path);
	ret = dw_i2c_gen_speed_config(dev, speed, &config);
	if (ret)
	return log_msg_ret("config", ret);
	dw_i2c_acpi_write_speed_config(ctx, &config);
	acpigen_pop_len(ctx);

	return 0;
	}

	struct acpi_ops dw_i2c_acpi_ops = {
	.fill_ssdt = dw_i2c_acpi_fill_ssdt,
	};

	static const struct udevice_id designware_i2c_pci_ids[] = {
	{ .compatible = "snps,designware-i2c-pci" },
	{ .compatible = "intel,apl-i2c", .data = INTEL_APL },
	{ }
	};

	U_BOOT_DRIVER(i2c_designware_pci) = {
	.name = "i2c_designware_pci",
	.id = UCLASS_I2C,
	.of_match = designware_i2c_pci_ids,
	.bind = designware_i2c_pci_bind,
	.ofdata_to_platdata = designware_i2c_pci_ofdata_to_platdata,
	.probe = designware_i2c_pci_probe,
	.priv_auto_alloc_size = sizeof(struct dw_i2c),
	.remove = designware_i2c_remove,
	.flags = DM_FLAG_OS_PREPARE,
	.ops = &designware_i2c_ops,
	ACPI_OPS_PTR(&dw_i2c_acpi_ops)
	};

	static struct pci_device_id designware_pci_supported[] = {
	/* Intel BayTrail has 7 I2C controller located on the PCI bus */
	{ PCI_VDEVICE(INTEL, 0x0f41) },
	{ PCI_VDEVICE(INTEL, 0x0f42) },
	{ PCI_VDEVICE(INTEL, 0x0f43) },
	{ PCI_VDEVICE(INTEL, 0x0f44) },
	{ PCI_VDEVICE(INTEL, 0x0f45) },
	{ PCI_VDEVICE(INTEL, 0x0f46) },
	{ PCI_VDEVICE(INTEL, 0x0f47) },
	{ PCI_VDEVICE(INTEL, 0x5aac), .driver_data = INTEL_APL },
	{ PCI_VDEVICE(INTEL, 0x5aae), .driver_data = INTEL_APL },
	{ PCI_VDEVICE(INTEL, 0x5ab0), .driver_data = INTEL_APL },
	{ PCI_VDEVICE(INTEL, 0x5ab2), .driver_data = INTEL_APL },
	{ PCI_VDEVICE(INTEL, 0x5ab4), .driver_data = INTEL_APL },
	{ PCI_VDEVICE(INTEL, 0x5ab6), .driver_data = INTEL_APL },
	{},
	};

	U_BOOT_PCI_DEVICE(i2c_designware_pci, designware_pci_supported);