diff options
Diffstat (limited to 'drivers/i2c/designware_i2c_pci.c')
| -rw-r--r-- | drivers/i2c/designware_i2c_pci.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/drivers/i2c/designware_i2c_pci.c b/drivers/i2c/designware_i2c_pci.c new file mode 100644 index 00000000000..11c98672265 --- /dev/null +++ b/drivers/i2c/designware_i2c_pci.c @@ -0,0 +1,215 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * (C) Copyright 2009 + * Vipin Kumar, STMicroelectronics, vipin.kumar@st.com. + * Copyright 2019 Google Inc + */ + +#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_of_to_plat(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, 0, 0, + PCI_REGION_TYPE, 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_of_to_plat(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_has_ofnode(dev)) + return 0; + + sprintf(name, "i2c_designware#%u", dev_seq(dev)); + 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]; + uint speed; + int ret; + + /* If no device-tree node, ignore this since we assume it isn't used */ + if (!dev_has_ofnode(dev)) + return 0; + + ret = acpi_device_path(dev, path, sizeof(path)); + if (ret) + return log_msg_ret("path", ret); + + 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 }, + { } +}; + +DM_DRIVER_ALIAS(i2c_designware_pci, intel_apl_i2c) + +U_BOOT_DRIVER(i2c_designware_pci) = { + .name = "i2c_designware_pci", + .id = UCLASS_I2C, + .of_match = designware_i2c_pci_ids, + .bind = designware_i2c_pci_bind, + .of_to_plat = designware_i2c_pci_of_to_plat, + .probe = designware_i2c_pci_probe, + .priv_auto = 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); |