Add a function to write an interrupt descriptor to the generated ACPI code.
Signed-off-by: Simon Glass sjg@chromium.org ---
Changes in v2: None Changes in v1: None
include/acpi/acpi_device.h | 15 +++++ lib/acpi/acpi_device.c | 118 +++++++++++++++++++++++++++++++++++++ test/dm/acpigen.c | 31 ++++++++++ 3 files changed, 164 insertions(+)
diff --git a/include/acpi/acpi_device.h b/include/acpi/acpi_device.h index 24895de0da..4f87cd003a 100644 --- a/include/acpi/acpi_device.h +++ b/include/acpi/acpi_device.h @@ -11,6 +11,8 @@
#include <linux/bitops.h>
+struct acpi_ctx; +struct irq; struct udevice;
/* ACPI descriptor values for common descriptors: SERIAL_BUS means I2C */ @@ -128,4 +130,17 @@ int acpi_device_scope(const struct udevice *dev, char *scope, int maxlen); */ enum acpi_dev_status acpi_device_status(const struct udevice *dev);
+/** + * acpi_device_write_interrupt_irq() - Write an interrupt descriptor + * + * This writes an ACPI interrupt descriptor for the given interrupt, converting + * fields as needed. + * + * @ctx: ACPI context pointer + * @req_irq: Interrupt to output + * @return 0 if OK, -ve on error + */ +int acpi_device_write_interrupt_irq(struct acpi_ctx *ctx, + const struct irq *req_irq); + #endif diff --git a/lib/acpi/acpi_device.c b/lib/acpi/acpi_device.c index 7b18cbf148..6b2fb7e47e 100644 --- a/lib/acpi/acpi_device.c +++ b/lib/acpi/acpi_device.c @@ -8,8 +8,10 @@
#include <common.h> #include <dm.h> +#include <irq.h> #include <log.h> #include <acpi/acpi_device.h> +#include <acpi/acpigen.h> #include <dm/acpi.h>
/** @@ -86,3 +88,119 @@ enum acpi_dev_status acpi_device_status(const struct udevice *dev) { return ACPI_DSTATUS_ALL_ON; } + +/** + * acpi_device_write_zero_len() - Write a placeholder word value + * + * @return pointer to the zero word (for fixing up later) + */ +static void *acpi_device_write_zero_len(struct acpi_ctx *ctx) +{ + u8 *p = acpigen_get_current(ctx); + + acpigen_emit_word(ctx, 0); + + return p; +} + +/** + * acpi_device_fill_from_len() - Fill in a length value + * + * This calculated the number of bytes since the provided @start and writes it + * to @ptr, which was previous returned by acpi_device_write_zero_len(). + * + * @ptr: Word to update + * @start: Start address to count from to calculated the length + */ +static void acpi_device_fill_from_len(struct acpi_ctx *ctx, char *ptr, + u8 *start) +{ + u16 len = acpigen_get_current(ctx) - start; + + ptr[0] = len & 0xff; + ptr[1] = (len >> 8) & 0xff; +} + +/** + * acpi_device_fill_len() - Fill in a length value, excluding the length itself + * + * Fill in the length field with the value calculated from after the 16bit + * field to acpigen current. This is useful since the length value does not + * include the length field itself. + * + * This calls acpi_device_fill_from_len() passing @ptr + 2 as @start + * + * @ptr: Word to update. + */ +static void acpi_device_fill_len(struct acpi_ctx *ctx, void *ptr) +{ + acpi_device_fill_from_len(ctx, ptr, ptr + sizeof(u16)); +} + +/* ACPI 6.3 section 6.4.3.6: Extended Interrupt Descriptor */ +static int acpi_device_write_interrupt(struct acpi_ctx *ctx, + const struct acpi_irq *irq) +{ + void *desc_length; + u8 flags; + + if (!irq->pin) + return -ENOENT; + + /* This is supported by GpioInt() but not Interrupt() */ + if (irq->polarity == ACPI_IRQ_ACTIVE_BOTH) + return -EINVAL; + + /* Byte 0: Descriptor Type */ + acpigen_emit_byte(ctx, ACPI_DESCRIPTOR_INTERRUPT); + + /* Byte 1-2: Length (filled in later) */ + desc_length = acpi_device_write_zero_len(ctx); + + /* + * Byte 3: Flags + * [7:5]: Reserved + * [4]: Wake (0=NO_WAKE 1=WAKE) + * [3]: Sharing (0=EXCLUSIVE 1=SHARED) + * [2]: Polarity (0=HIGH 1=LOW) + * [1]: Mode (0=LEVEL 1=EDGE) + * [0]: Resource (0=PRODUCER 1=CONSUMER) + */ + flags = 1 << 0; /* ResourceConsumer */ + if (irq->mode == ACPI_IRQ_EDGE_TRIGGERED) + flags |= 1 << 1; + if (irq->polarity == ACPI_IRQ_ACTIVE_LOW) + flags |= 1 << 2; + if (irq->shared == ACPI_IRQ_SHARED) + flags |= 1 << 3; + if (irq->wake == ACPI_IRQ_WAKE) + flags |= 1 << 4; + acpigen_emit_byte(ctx, flags); + + /* Byte 4: Interrupt Table Entry Count */ + acpigen_emit_byte(ctx, 1); + + /* Byte 5-8: Interrupt Number */ + acpigen_emit_dword(ctx, irq->pin); + + /* Fill in Descriptor Length (account for len word) */ + acpi_device_fill_len(ctx, desc_length); + + return 0; +} + +int acpi_device_write_interrupt_irq(struct acpi_ctx *ctx, + const struct irq *req_irq) +{ + struct acpi_irq irq; + int ret; + + ret = irq_get_acpi(req_irq, &irq); + if (ret) + return log_msg_ret("get", ret); + ret = acpi_device_write_interrupt(ctx, &irq); + if (ret) + return log_msg_ret("write", ret); + + return 0; +} diff --git a/test/dm/acpigen.c b/test/dm/acpigen.c index 68f2b73132..ab1261db9f 100644 --- a/test/dm/acpigen.c +++ b/test/dm/acpigen.c @@ -8,8 +8,10 @@
#include <common.h> #include <dm.h> +#include <irq.h> #include <malloc.h> #include <acpi/acpigen.h> +#include <acpi/acpi_device.h> #include <asm/unaligned.h> #include <dm/acpi.h> #include <dm/test.h> @@ -63,3 +65,32 @@ static int dm_test_acpi_emit_simple(struct unit_test_state *uts) return 0; } DM_TEST(dm_test_acpi_emit_simple, 0); + +/* Test emitting an interrupt descriptor */ +static int dm_test_acpi_interrupt(struct unit_test_state *uts) +{ + struct acpi_ctx *ctx; + struct udevice *dev; + struct irq irq; + u8 *ptr; + + ut_assertok(alloc_context(&ctx)); + + ptr = acpigen_get_current(ctx); + + ut_assertok(uclass_first_device_err(UCLASS_TEST_FDT, &dev)); + ut_assertok(irq_get_by_index(dev, 0, &irq)); + + ut_assertok(acpi_device_write_interrupt_irq(ctx, &irq)); + ut_asserteq(9, acpigen_get_current(ctx) - ptr); + ut_asserteq(ACPI_DESCRIPTOR_INTERRUPT, ptr[0]); + ut_asserteq(6, get_unaligned((u16 *)(ptr + 1))); + ut_asserteq(0x19, ptr[3]); + ut_asserteq(1, ptr[4]); + ut_asserteq(3, get_unaligned((u32 *)(ptr + 5))); + + free_context(&ctx); + + return 0; +} +DM_TEST(dm_test_acpi_interrupt, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);