From b7d79cddf0287a2e925d2003ef8d0cde6bbbae2a Mon Sep 17 00:00:00 2001 From: Aaron Durbin Date: Mon, 22 Jan 2018 21:31:48 -0700 Subject: drives/i2c/designware: incorporate device_operations support In ramstage the device_operations are needed for the i2c designware host controller. Move the intel/common/block/i2c implementation into the generic driver so other platforms can take advantage of it. BUG=b:72121803 Change-Id: Id249933fadcc016bfba00e7a6d65f56dfc220724 Signed-off-by: Aaron Durbin Reviewed-on: https://review.coreboot.org/23372 Tested-by: build bot (Jenkins) Reviewed-by: Martin Roth Reviewed-by: Furquan Shaikh Reviewed-by: Subrata Banik --- src/drivers/i2c/designware/dw_i2c.c | 124 +++++++++++++++++++++++++++++++++++- src/drivers/i2c/designware/dw_i2c.h | 25 ++++++++ 2 files changed, 146 insertions(+), 3 deletions(-) (limited to 'src/drivers/i2c') diff --git a/src/drivers/i2c/designware/dw_i2c.c b/src/drivers/i2c/designware/dw_i2c.c index 75f8871d56..aeddbbcf01 100644 --- a/src/drivers/i2c/designware/dw_i2c.c +++ b/src/drivers/i2c/designware/dw_i2c.c @@ -19,10 +19,8 @@ #include #include #include +#include #include -#include -#include -#include #include #include #include "dw_i2c.h" @@ -726,3 +724,123 @@ int dw_i2c_init(unsigned int bus, const struct dw_i2c_bus_config *bcfg) 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( + const struct dw_i2c_speed_config *config) +{ + if (!config) + return; + if (!config->scl_lcnt && !config->scl_hcnt && !config->sda_hold) + return; + + if (config->speed >= I2C_SPEED_HIGH) + acpigen_write_name("HSCN"); + else if (config->speed >= I2C_SPEED_FAST_PLUS) + acpigen_write_name("FPCN"); + else if (config->speed >= I2C_SPEED_FAST) + acpigen_write_name("FMCN"); + else + acpigen_write_name("SSCN"); + + /* Package () { scl_lcnt, scl_hcnt, sda_hold } */ + acpigen_write_package(3); + acpigen_write_word(config->scl_hcnt); + acpigen_write_word(config->scl_lcnt); + acpigen_write_dword(config->sda_hold); + acpigen_pop_len(); +} + +/* + * The device should already be enabled and out of reset, + * either from early init in coreboot or SiliconInit in FSP. + */ +void dw_i2c_dev_init(struct device *dev) +{ + const struct dw_i2c_bus_config *config; + int bus = dw_i2c_soc_dev_to_bus(dev); + + if (bus < 0) + return; + + config = dw_i2c_get_soc_cfg(bus, dev); + + if (!config) + return; + + dw_i2c_init(bus, config); +} + +/* + * Generate I2C timing information into the SSDT for the OS driver to consume, + * optionally applying override values provided by the caller. + */ +void dw_i2c_acpi_fill_ssdt(struct device *dev) +{ + const struct dw_i2c_bus_config *bcfg; + uintptr_t dw_i2c_addr; + struct dw_i2c_speed_config sgen; + enum i2c_speed speeds[DW_I2C_SPEED_CONFIG_COUNT] = { + I2C_SPEED_STANDARD, + I2C_SPEED_FAST, + I2C_SPEED_FAST_PLUS, + I2C_SPEED_HIGH, + }; + int i, bus; + const char *path; + + if (!dev->enabled) + return; + + bus = dw_i2c_soc_dev_to_bus(dev); + + if (bus < 0) + return; + + bcfg = dw_i2c_get_soc_cfg(bus, dev); + + if (!bcfg) + return; + + dw_i2c_addr = dw_i2c_base_address(bus); + if (!dw_i2c_addr) + return; + + path = acpi_device_path(dev); + if (!path) + return; + + acpigen_write_scope(path); + + /* Report timing values for the OS driver */ + for (i = 0; i < DW_I2C_SPEED_CONFIG_COUNT; i++) { + /* Generate speed config. */ + if (dw_i2c_gen_speed_config(dw_i2c_addr, speeds[i], bcfg, + &sgen) < 0) + continue; + + /* Generate ACPI based on selected speed config */ + dw_i2c_acpi_write_speed_config(&sgen); + } + + acpigen_pop_len(); +} + +static int dw_i2c_dev_transfer(struct device *dev, + const struct i2c_msg *msg, size_t count) +{ + return dw_i2c_transfer(dw_i2c_soc_dev_to_bus(dev), msg, count); +} + +const struct i2c_bus_operations dw_i2c_bus_ops = { + .transfer = dw_i2c_dev_transfer, +}; diff --git a/src/drivers/i2c/designware/dw_i2c.h b/src/drivers/i2c/designware/dw_i2c.h index 83e0e6d5e6..c97ed7785f 100644 --- a/src/drivers/i2c/designware/dw_i2c.h +++ b/src/drivers/i2c/designware/dw_i2c.h @@ -137,4 +137,29 @@ int dw_i2c_transfer(unsigned int bus, const struct i2c_msg *segments, size_t count); +/* + * Map an i2c host controller device to a logical bus number. + * Return value: + * -1 = failure + * >=0 = logical bus number + */ +int dw_i2c_soc_dev_to_bus(struct device *dev); + +/* + * Common device_operations implementation to initialize the i2c host + * controller. + */ +void dw_i2c_dev_init(struct device *dev); + +/* + * Common device_operations implementation to fill ACPI SSDT table for i2c + * host controller. + */ +void dw_i2c_acpi_fill_ssdt(struct device *dev); + +/* + * Common device_operations implementation for i2c host controller ops. + */ +extern const struct i2c_bus_operations dw_i2c_bus_ops; + #endif /* __DRIVERS_I2C_DESIGNWARE_I2C_H__ */ -- cgit v1.2.3