Hi Simon, -----"Simon Glass" <s...@chromium.org> schrieb: ----- > Betreff: [PATCH v1 28/43] i2c: designware_i2c: Support ACPI table generation > > Update the PCI driver to generate ACPI information so that Linux has the > full information about each I2C bus. > > Signed-off-by: Simon Glass <s...@chromium.org> > > --- > > Changes in v1: > - Capitalise ACPI_OPS_PTR > > drivers/i2c/designware_i2c.c | 25 ++++++++ > drivers/i2c/designware_i2c.h | 15 +++++ > drivers/i2c/designware_i2c_pci.c | 104 ++++++++++++++++++++++++++++++- > 3 files changed, 143 insertions(+), 1 deletion(-) > > diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c > index 44a1f33398..630938743f 100644 > --- a/drivers/i2c/designware_i2c.c > +++ b/drivers/i2c/designware_i2c.c > @@ -333,6 +333,31 @@ static int _dw_i2c_set_bus_speed(struct dw_i2c *priv, > struct i2c_regs *i2c_base, > /* Restore back i2c now speed set */ > if (ena == IC_ENABLE_0B) > dw_i2c_enable(i2c_base, true); > + if (priv) > + priv->config = config; > + return 0; > +} > + > +int dw_i2c_gen_speed_config(const struct udevice *dev, int speed_hz, > + struct dw_i2c_speed_config *config) > +{ > + struct dw_i2c *priv = dev_get_priv(dev); > + ulong rate; > + int ret; > + > +#if CONFIG_IS_ENABLED(CLK) > + rate = clk_get_rate(&priv->clk); > + if (IS_ERR_VALUE(rate)) > + return log_msg_ret("clk", -EINVAL); > +#else > + rate = IC_CLK; > +#endif > + > + ret = calc_bus_speed(priv, priv->regs, speed_hz, rate, config); > + if (ret) > + printf("%s: ret=%d\n", __func__, ret); > + if (ret) > + return log_msg_ret("calc_bus_speed", ret); > > return 0; > } > diff --git a/drivers/i2c/designware_i2c.h b/drivers/i2c/designware_i2c.h > index dc9a6ccb63..d87a3bff93 100644 > --- a/drivers/i2c/designware_i2c.h > +++ b/drivers/i2c/designware_i2c.h > @@ -205,6 +205,7 @@ struct dw_i2c { > #if CONFIG_IS_ENABLED(CLK) > struct clk clk; > #endif > + struct dw_i2c_speed_config config; > }; > > extern const struct dm_i2c_ops designware_i2c_ops; > @@ -213,4 +214,18 @@ int designware_i2c_probe(struct udevice *bus); > int designware_i2c_remove(struct udevice *dev); > int designware_i2c_ofdata_to_platdata(struct udevice *bus); > > +/** > + * dw_i2c_gen_speed_config() - Calculate config info from requested speed1 > + * > + * Calculate the speed config from the given @speed_hz and return it so that > + * it can be incorporated in ACPI tables > + * > + * @dev: I2C bus to check > + * @speed_hz: Requested speed in Hz > + * @config: Returns config to use for that speed > + * @return 0 if OK, -ve on error > + */ > +int dw_i2c_gen_speed_config(const struct udevice *dev, int speed_hz, > + struct dw_i2c_speed_config *config); > + > #endif /* __DW_I2C_H_ */ > diff --git a/drivers/i2c/designware_i2c_pci.c > b/drivers/i2c/designware_i2c_pci.c > index bd34ec0b47..d5108e9064 100644 > --- a/drivers/i2c/designware_i2c_pci.c > +++ b/drivers/i2c/designware_i2c_pci.c > @@ -9,7 +9,12 @@ > #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 { > @@ -87,6 +92,8 @@ 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: > @@ -100,13 +107,107 @@ static int designware_i2c_pci_bind(struct udevice *dev) > * be possible. We cannot use static data in drivers since they may be > * used in SPL or before relocation. > */ > - dev->req_seq = gd->arch.dw_i2c_num_cards++; > + 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); > +}
This function is rather generic, and probably the same for any I2C controller. Is the intention to implement it for Designware as a first step and move it to a generic place if the need arises, or should it stay here? > + > +/* > + * 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]; > + int size, i; > + 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); > + > + if (0) { This seems like some left-over debugging code ... ? > + acpigen_write_scope(ctx, path); > + for (i = 0; i < size; i++) { > + ret = dw_i2c_gen_speed_config(dev, speeds[i], &config); > + if (ret) > + return log_msg_ret("config", ret); > + dw_i2c_acpi_write_speed_config(ctx, &config); > + } > + } else { > + uint speed; > + > + 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 }, > @@ -124,6 +225,7 @@ U_BOOT_DRIVER(i2c_designware_pci) = { > .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[] = { > -- > 2.27.0.290.gba653c62da-goog regards, Wolfgang