Add a function to write a SPI descriptor to the generated ACPI code.
Signed-off-by: Simon Glass sjg@chromium.org ---
Changes in v3: - Make acpi_device_write_spi() static - Add an extra comment about scope to acpi_device_set_spi() - Use BIT() in a few places - Resist the temptation to go to >80 characters
Changes in v2: - Fix memset of SPI descriptor
drivers/spi/sandbox_spi.c | 11 ++++ include/acpi/acpi_device.h | 36 +++++++++++ include/spi.h | 4 +- lib/acpi/acpi_device.c | 124 +++++++++++++++++++++++++++++++++++++ test/dm/acpigen.c | 36 +++++++++++ 5 files changed, 209 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/sandbox_spi.c b/drivers/spi/sandbox_spi.c index b0a46c8868..4264acc953 100644 --- a/drivers/spi/sandbox_spi.c +++ b/drivers/spi/sandbox_spi.c @@ -21,6 +21,7 @@ #include <linux/errno.h> #include <asm/spi.h> #include <asm/state.h> +#include <dm/acpi.h> #include <dm/device-internal.h>
#ifndef CONFIG_SPI_IDLE_VAL @@ -133,6 +134,15 @@ static int sandbox_spi_get_mmap(struct udevice *dev, ulong *map_basep, return 0; }
+static int sandbox_spi_get_name(const struct udevice *dev, char *out_name) +{ + return acpi_copy_name(out_name, "SSPI"); +} + +struct acpi_ops sandbox_spi_acpi_ops = { + .get_name = sandbox_spi_get_name, +}; + static const struct dm_spi_ops sandbox_spi_ops = { .xfer = sandbox_spi_xfer, .set_speed = sandbox_spi_set_speed, @@ -151,4 +161,5 @@ U_BOOT_DRIVER(spi_sandbox) = { .id = UCLASS_SPI, .of_match = sandbox_spi_ids, .ops = &sandbox_spi_ops, + ACPI_OPS_PTR(&sandbox_spi_acpi_ops) }; diff --git a/include/acpi/acpi_device.h b/include/acpi/acpi_device.h index f738b03d58..c0c96183e4 100644 --- a/include/acpi/acpi_device.h +++ b/include/acpi/acpi_device.h @@ -10,6 +10,7 @@ #define __ACPI_DEVICE_H
#include <i2c.h> +#include <spi.h> #include <linux/bitops.h>
struct acpi_ctx; @@ -207,6 +208,29 @@ struct acpi_i2c { const char *resource; };
+/** + * struct acpi_spi - representation of an ACPI SPI device + * + * @device_select: Chip select used by this device (typically 0) + * @device_select_polarity: Polarity for the device + * @wire_mode: Number of wires used for SPI + * @speed: Bus speed in Hz + * @data_bit_length: Word length for SPI (typically 8) + * @clock_phase: Clock phase to capture data + * @clock_polarity: Bus polarity + * @resource: Resource name for the SPI controller + */ +struct acpi_spi { + u16 device_select; + enum spi_polarity device_select_polarity; + enum spi_wire_mode wire_mode; + unsigned int speed; + u8 data_bit_length; + enum spi_clock_phase clock_phase; + enum spi_polarity clock_polarity; + const char *resource; +}; + /** * acpi_device_path() - Get the full path to an ACPI device * @@ -306,4 +330,16 @@ int acpi_device_write_interrupt_or_gpio(struct acpi_ctx *ctx, */ int acpi_device_write_i2c_dev(struct acpi_ctx *ctx, const struct udevice *dev);
+/** + * acpi_device_write_spi_dev() - Write a SPI device to ACPI + * + * This writes a serial bus descriptor for the SPI device so that ACPI can use + * it + * + * @ctx: ACPI context pointer + * @dev: SPI device to write + * @return 0 if OK, -ve on error + */ +int acpi_device_write_spi_dev(struct acpi_ctx *ctx, const struct udevice *dev); + #endif diff --git a/include/spi.h b/include/spi.h index 5cc6d6e008..f34533f54e 100644 --- a/include/spi.h +++ b/include/spi.h @@ -13,8 +13,8 @@ #include <linux/bitops.h>
/* SPI mode flags */ -#define SPI_CPHA BIT(0) /* clock phase */ -#define SPI_CPOL BIT(1) /* clock polarity */ +#define SPI_CPHA BIT(0) /* clock phase (1 = SPI_CLOCK_PHASE_SECOND) */ +#define SPI_CPOL BIT(1) /* clock polarity (1 = SPI_POLARITY_HIGH) */ #define SPI_MODE_0 (0|0) /* (original MicroWire) */ #define SPI_MODE_1 (0|SPI_CPHA) #define SPI_MODE_2 (SPI_CPOL|0) diff --git a/lib/acpi/acpi_device.c b/lib/acpi/acpi_device.c index 40d1a82d27..38101c8b96 100644 --- a/lib/acpi/acpi_device.c +++ b/lib/acpi/acpi_device.c @@ -488,3 +488,127 @@ int acpi_device_write_i2c_dev(struct acpi_ctx *ctx, const struct udevice *dev)
return 0; } + +#ifdef CONFIG_SPI +/* ACPI 6.1 section 6.4.3.8.2.2 - SpiSerialBus() */ +static void acpi_device_write_spi(struct acpi_ctx *ctx, const struct acpi_spi *spi) +{ + void *desc_length, *type_length; + u16 flags = 0; + + /* Byte 0: Descriptor Type */ + acpigen_emit_byte(ctx, ACPI_DESCRIPTOR_SERIAL_BUS); + + /* Byte 1+2: Length (filled in later) */ + desc_length = acpi_device_write_zero_len(ctx); + + /* Byte 3: Revision ID */ + acpigen_emit_byte(ctx, ACPI_SPI_SERIAL_BUS_REVISION_ID); + + /* Byte 4: Resource Source Index is Reserved */ + acpigen_emit_byte(ctx, 0); + + /* Byte 5: Serial Bus Type is SPI */ + acpigen_emit_byte(ctx, ACPI_SERIAL_BUS_TYPE_SPI); + + /* + * Byte 6: Flags + * [7:2]: 0 => Reserved + * [1]: 1 => ResourceConsumer + * [0]: 0 => ControllerInitiated + */ + acpigen_emit_byte(ctx, BIT(1)); + + /* + * Byte 7-8: Type Specific Flags + * [15:2]: 0 => Reserveda + * [1]: 0 => ActiveLow, 1 => ActiveHigh + * [0]: 0 => FourWire, 1 => ThreeWire + */ + if (spi->wire_mode == SPI_3_WIRE_MODE) + flags |= BIT(0); + if (spi->device_select_polarity == SPI_POLARITY_HIGH) + flags |= BIT(1); + acpigen_emit_word(ctx, flags); + + /* Byte 9: Type Specific Revision ID */ + acpigen_emit_byte(ctx, ACPI_SPI_TYPE_SPECIFIC_REVISION_ID); + + /* Byte 10-11: SPI Type Data Length */ + type_length = acpi_device_write_zero_len(ctx); + + /* Byte 12-15: Connection Speed */ + acpigen_emit_dword(ctx, spi->speed); + + /* Byte 16: Data Bit Length */ + acpigen_emit_byte(ctx, spi->data_bit_length); + + /* Byte 17: Clock Phase */ + acpigen_emit_byte(ctx, spi->clock_phase); + + /* Byte 18: Clock Polarity */ + acpigen_emit_byte(ctx, spi->clock_polarity); + + /* Byte 19-20: Device Selection */ + acpigen_emit_word(ctx, spi->device_select); + + /* Fill in Type Data Length */ + acpi_device_fill_len(ctx, type_length); + + /* Byte 21+: ResourceSource String */ + acpigen_emit_string(ctx, spi->resource); + + /* Fill in SPI Descriptor Length */ + acpi_device_fill_len(ctx, desc_length); +} + +/** + * acpi_device_set_spi() - Set up an ACPI SPI struct from a device + * + * The value of @scope is not copied, but only referenced. This implies the + * caller has to ensure it stays valid for the lifetime of @spi. + * + * @dev: SPI device to convert + * @spi: Place to put the new structure + * @scope: Scope of the SPI device (this is the controller path) + * @return 0 (always) + */ +static int acpi_device_set_spi(const struct udevice *dev, struct acpi_spi *spi, + const char *scope) +{ + struct dm_spi_slave_platdata *plat; + struct spi_slave *slave = dev_get_parent_priv(dev); + + plat = dev_get_parent_platdata(slave->dev); + memset(spi, '\0', sizeof(*spi)); + spi->device_select = plat->cs; + spi->device_select_polarity = SPI_POLARITY_LOW; + spi->wire_mode = SPI_4_WIRE_MODE; + spi->speed = plat->max_hz; + spi->data_bit_length = slave->wordlen; + spi->clock_phase = plat->mode & SPI_CPHA ? + SPI_CLOCK_PHASE_SECOND : SPI_CLOCK_PHASE_FIRST; + spi->clock_polarity = plat->mode & SPI_CPOL ? + SPI_POLARITY_HIGH : SPI_POLARITY_LOW; + spi->resource = scope; + + return 0; +} + +int acpi_device_write_spi_dev(struct acpi_ctx *ctx, const struct udevice *dev) +{ + char scope[ACPI_PATH_MAX]; + struct acpi_spi spi; + int ret; + + ret = acpi_device_scope(dev, scope, sizeof(scope)); + if (ret) + return log_msg_ret("scope", ret); + ret = acpi_device_set_spi(dev, &spi, scope); + if (ret) + return log_msg_ret("set", ret); + acpi_device_write_spi(ctx, &spi); + + return 0; +} +#endif /* CONFIG_SPI */ diff --git a/test/dm/acpigen.c b/test/dm/acpigen.c index 53842be55a..571510722d 100644 --- a/test/dm/acpigen.c +++ b/test/dm/acpigen.c @@ -302,3 +302,39 @@ static int dm_test_acpi_i2c(struct unit_test_state *uts) return 0; } DM_TEST(dm_test_acpi_i2c, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT); + +/* Test emitting a SPI descriptor */ +static int dm_test_acpi_spi(struct unit_test_state *uts) +{ + struct acpi_ctx *ctx; + struct udevice *dev; + u8 *ptr; + + ut_assertok(alloc_context(&ctx)); + + ptr = acpigen_get_current(ctx); + + ut_assertok(uclass_first_device_err(UCLASS_SPI_FLASH, &dev)); + ut_assertok(acpi_device_write_spi_dev(ctx, dev)); + ut_asserteq(31, acpigen_get_current(ctx) - ptr); + ut_asserteq(ACPI_DESCRIPTOR_SERIAL_BUS, ptr[0]); + ut_asserteq(28, get_unaligned((u16 *)(ptr + 1))); + ut_asserteq(ACPI_SPI_SERIAL_BUS_REVISION_ID, ptr[3]); + ut_asserteq(0, ptr[4]); + ut_asserteq(ACPI_SERIAL_BUS_TYPE_SPI, ptr[5]); + ut_asserteq(2, ptr[6]); + ut_asserteq(0, get_unaligned((u16 *)(ptr + 7))); + ut_asserteq(ACPI_SPI_TYPE_SPECIFIC_REVISION_ID, ptr[9]); + ut_asserteq(9, get_unaligned((u16 *)(ptr + 10))); + ut_asserteq(40000000, get_unaligned((u32 *)(ptr + 12))); + ut_asserteq(8, ptr[16]); + ut_asserteq(0, ptr[17]); + ut_asserteq(0, ptr[18]); + ut_asserteq(0, get_unaligned((u16 *)(ptr + 19))); + ut_asserteq_str("\_SB.SSPI", (char *)ptr + 21); + + free_context(&ctx); + + return 0; +} +DM_TEST(dm_test_acpi_spi, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);