diff options
author | Simon Glass <sjg@chromium.org> | 2020-07-07 13:11:43 -0600 |
---|---|---|
committer | Bin Meng <bmeng.cn@gmail.com> | 2020-07-17 14:32:24 +0800 |
commit | ff715c6f4f7a3181fcc6a45907bb8bf0c8c6f08f (patch) | |
tree | fc8fa40ad52e564861ff98e40b38c71b2651347e /lib | |
parent | 61cc93396a54c1c3fcace092c83def70f3843c2a (diff) |
acpi: Support generation of interrupt descriptor
Add a function to write an interrupt descriptor to the generated ACPI
code.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/acpi/acpi_device.c | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/lib/acpi/acpi_device.c b/lib/acpi/acpi_device.c index 60f4fd8cd5..d854a45cbc 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 +88,120 @@ enum acpi_dev_status acpi_device_status(const struct udevice *dev) { return ACPI_DSTATUS_ALL_ON; } + +/** + * largeres_write_len_f() - Write a placeholder word value + * + * Write a forward length for a large resource (2 bytes) + * + * @return pointer to the zero word (for fixing up later) + */ +static void *largeres_write_len_f(struct acpi_ctx *ctx) +{ + u8 *p = acpigen_get_current(ctx); + + acpigen_emit_word(ctx, 0); + + return p; +} + +/** + * largeres_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 largeres_write_len_f(). + * + * @ptr: Word to update + * @start: Start address to count from to calculated the length + */ +static void largeres_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; +} + +/** + * largeres_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_largeres_fill_len() passing @ptr + 2 as @start + * + * @ptr: Word to update. + */ +static void largeres_fill_len(struct acpi_ctx *ctx, void *ptr) +{ + largeres_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 = largeres_write_len_f(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 = BIT(0); /* ResourceConsumer */ + if (irq->mode == ACPI_IRQ_EDGE_TRIGGERED) + flags |= BIT(1); + if (irq->polarity == ACPI_IRQ_ACTIVE_LOW) + flags |= BIT(2); + if (irq->shared == ACPI_IRQ_SHARED) + flags |= BIT(3); + if (irq->wake == ACPI_IRQ_WAKE) + flags |= BIT(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) */ + largeres_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; +} |