Re: [PATCH v2 28/44] i2c: designware_i2c: Support ACPI table generation

Hi Simon,

-----"Simon Glass" sjg@chromium.org schrieb: -----

Betreff: [PATCH v2 28/44] 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 sjg@chromium.org

Reviewed-by: Heiko Schocher hs@denx.de

Changes in v2:

• Add a few blank lines
• Drop dead code behind if (0)

Changes in v1:

• Capitalise ACPI_OPS_PTR

drivers/i2c/designware_i2c.c | 26 +++++++++ drivers/i2c/designware_i2c.h | 15 +++++ drivers/i2c/designware_i2c_pci.c | 96 +++++++++++++++++++++++++++++++- 3 files changed, 136 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c index 44a1f33398..cf892c69d9 100644 --- a/drivers/i2c/designware_i2c.c +++ b/drivers/i2c/designware_i2c.c @@ -333,6 +333,32 @@ 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

Nit: is "speed1" a typo?

• • 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..d0d869c81a 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 +92,9 @@ 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 +108,98 @@ 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);

+}

+/*

• • 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 }, @@ -124,6 +217,7 @@ 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[] = {

2.27.0.383.g050319c2ae-goog

Reviewed-by: Wolfgang Wallner wolfgang.wallner@br-automation.com