Antwort: [PATCH v2 32/39] irq: Add a method to convert an interrupt to ACPI
Wolfgang Wallner
wolfgang.wallner at br-automation.com
Wed Mar 18 17:17:54 CET 2020
Hi Simon,
"Simon Glass" <sjg at chromium.org> schrieb am 09.03.2020 04:44:56:
> Von: "Simon Glass" <sjg at chromium.org>
> An: "U-Boot Mailing List" <u-boot at lists.denx.de>,
> Kopie: "Bin Meng" <bmeng.cn at gmail.com>, "Wolfgang Wallner"
> <wolfgang.wallner at br-automation.com>, "Andy Shevchenko"
> <andriy.shevchenko at linux.intel.com>, "Simon Glass" <sjg at chromium.org>
> Datum: 09.03.2020 04:46
> Betreff: [PATCH v2 32/39] irq: Add a method to convert an interrupt to
ACPI
>
> When generating ACPI tables we need to convert IRQs in U-Boot to the
ACPI
> structures required by ACPI. This is a SoC-specific conversion and
cannot
> be handled by generic code, so add a new IRQ method to do the
conversion.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> Changes in v2: None
>
> drivers/misc/irq-uclass.c | 18 +++++++-
> include/acpi_device.h | 27 +++++++++++
> include/irq.h | 41 +++++++++++++++++
> lib/acpi/acpi_device.c | 94 +++++++++++++++++++++++++++++++++++++++
> 4 files changed, 178 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/misc/irq-uclass.c b/drivers/misc/irq-uclass.c
> index 61aa10e465..b4a8b7b429 100644
> --- a/drivers/misc/irq-uclass.c
> +++ b/drivers/misc/irq-uclass.c
> @@ -153,8 +153,6 @@ int irq_request(struct udevice *dev, struct irq
*irq)
> const struct irq_ops *ops;
>
> log_debug("(dev=%p, irq=%p)\n", dev, irq);
> - if (!irq)
> - return 0;
Why is this code dropped?
> ops = irq_get_ops(dev);
>
> irq->dev = dev;
> @@ -176,6 +174,22 @@ int irq_first_device_type(enum irq_dev_t type,
> struct udevice **devp)
> return 0;
> }
>
> +#if CONFIG_IS_ENABLED(ACPIGEN)
> +int irq_get_acpi(const struct irq *irq, struct acpi_irq *acpi_irq)
> +{
> + struct irq_ops *ops;
> +
> + if (!irq_is_valid(irq))
> + return -EINVAL;
> +
> + ops = irq_get_ops(irq->dev);
> + if (!ops->get_acpi)
> + return -ENOSYS;
> +
> + return ops->get_acpi(irq, acpi_irq);
> +}
> +#endif
> +
> UCLASS_DRIVER(irq) = {
> .id = UCLASS_IRQ,
> .name = "irq",
> diff --git a/include/acpi_device.h b/include/acpi_device.h
> index acd26c0f54..50ba9b66aa 100644
> --- a/include/acpi_device.h
> +++ b/include/acpi_device.h
> @@ -545,6 +545,33 @@ int acpi_dp_write(struct acpi_ctx *ctx, struct
> acpi_dp *table);
> int acpi_device_write_gpio_desc(struct acpi_ctx *ctx,
> const struct gpio_desc *desc);
>
> +/**
> + * acpi_device_write_interrupt_irq() - Write an interrupt to ACPI
> + *
> + * This creates an interrupt descriptor for an interrupt, including
> information
> + * ACPI needs to use it.
> + *
> + * @req_irq: Interrupt to write
> + * @return 0 if OK, -ve on error
> + */
> +int acpi_device_write_interrupt_irq(struct acpi_ctx *ctx,
> + const struct irq *req_irq);
> +
> +/**
> + * acpi_device_write_interrupt_or_gpio() - Write interrupt or GPIO to
ACPI
> + *
> + * This reads the an interrupt from the device tree, if available. If
not it
typo: "the an"
The description of what this function should do is rather vague.
At least I'm not sure how it is meant to work.
> + * reads the first GPIO with the name @prop.
> + *
> + * If an interrupt is found, that is written to ACPI. If not, but an
GPIO is
> + * found, that is written.
> + *
> + * @return 0 if OK, -ve if neither an interrupt nor a GPIO could
befound, or
> + * some other error occurred
> + */
> +int acpi_device_write_interrupt_or_gpio(struct acpi_ctx *ctx,
> + struct udevice *dev, const char *prop);
> +
> /**
> * acpi_device_write_i2c_dev() - Write an I2C device to ACPI, including
> * information ACPI needs to use it.
> diff --git a/include/irq.h b/include/irq.h
> index d4948e6dc4..8527e4dd79 100644
> --- a/include/irq.h
> +++ b/include/irq.h
> @@ -8,6 +8,7 @@
> #ifndef __irq_H
> #define __irq_H
>
> +struct acpi_irq;
> struct ofnode_phandle_args;
>
> /*
> @@ -26,10 +27,12 @@ enum irq_dev_t {
> *
> * @dev: IRQ device that handles this irq
> * @id: ID to identify this irq with the device
> + * @flags: Flags associated with this interrupt (IRQ_TYPE_...)
> */
> struct irq {
> struct udevice *dev;
> ulong id;
> + ulong flags;
> };
>
> /**
> @@ -121,10 +124,36 @@ struct irq_ops {
> * @return 0 if OK, or a negative error code.
> */
> int (*free)(struct irq *irq);
> +
> +#if CONFIG_IS_ENABLED(ACPIGEN)
> + /**
> + * get_acpi() - Get the ACPI info for an irq
> + *
> + * This converts a irq to an ACPI structure for adding to the ACPI
> + * tables.
> + *
> + * @irq: irq to convert
> + * @acpi_irq: Output ACPI interrupt information
> + * @return ACPI pin number or -ve on error
> + */
> + int (*get_acpi)(const struct irq *irq, struct acpi_irq *acpi_irq);
> +#endif
> };
>
> #define irq_get_ops(dev) ((struct irq_ops *)(dev)->driver->ops)
>
> +/**
> + * irq_is_valid() - Check if an IRQ is valid
> + *
> + * @irq: IRQ description containing device and ID, e.g. previously
> + * returned by irq_get_by_index()
> + * @return true if valid, false if not
> + */
> +static inline bool irq_is_valid(const struct irq *irq)
> +{
> + return irq->dev != NULL;
> +}
> +
> /**
> * irq_route_pmc_gpio_gpe() - Get the GPIO for an event
> *
> @@ -225,4 +254,16 @@ int irq_free(struct irq *irq);
> */
> int irq_first_device_type(enum irq_dev_t type, struct udevice **devp);
>
> +/**
> + * irq_get_acpi() - Get the ACPI info for an irq
> + *
> + * This converts a irq to an ACPI structure for adding to the ACPI
> + * tables.
> + *
> + * @irq: irq to convert
> + * @acpi_irq: Output ACPI interrupt information
> + * @return ACPI pin number or -ve on error
> + */
> +int irq_get_acpi(const struct irq *irq, struct acpi_irq *acpi_irq);
> +
> #endif
> diff --git a/lib/acpi/acpi_device.c b/lib/acpi/acpi_device.c
> index adc32f1216..aa5edfe807 100644
> --- a/lib/acpi/acpi_device.c
> +++ b/lib/acpi/acpi_device.c
> @@ -154,6 +154,58 @@ int acpi_device_status(const struct udevice *dev)
> return ACPI_STATUS_DEVICE_ALL_ON;
> }
>
> +/* ACPI 6.1 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 || !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;
> +}
> +
> /* ACPI 6.1 section 6.4.3.8.1 - GPIO Interrupt or I/O */
> int acpi_device_write_gpio(struct acpi_ctx *ctx, const struct
> acpi_gpio *gpio)
> {
> @@ -304,6 +356,48 @@ int acpi_device_write_gpio_desc(struct acpi_ctx
*ctx,
> 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;
> +}
> +
> +int acpi_device_write_interrupt_or_gpio(struct acpi_ctx *ctx,
> + struct udevice *dev, const char *prop)
> +{
> + struct irq req_irq;
> + int ret;
> +
> + ret = irq_get_by_index(dev, 0, &req_irq);
> + if (!ret) {
> + ret = acpi_device_write_interrupt_irq(ctx, &req_irq);
> + if (ret)
> + return log_msg_ret("irq", ret);
> + } else {
> + struct gpio_desc req_gpio;
> +
> + ret = gpio_request_by_name(dev, prop, 0, &req_gpio,
> + GPIOD_IS_IN);
> + if (ret)
> + return log_msg_ret("no gpio", ret);
> + ret = acpi_device_write_gpio_desc(ctx, &req_gpio);
> + if (ret)
> + return log_msg_ret("gpio", ret);
> + }
Both code paths set the index value hardcoded to 0.
Why is that? Would other indices not make sense?
> +
> + return 0;
> +}
> +
> /* ACPI 6.1 section 6.4.3.8.2.1 - I2cSerialBus() */
> static void acpi_device_write_i2c(struct acpi_ctx *ctx,
> const struct acpi_i2c *i2c)
> --
> 2.25.1.481.gfbce0eb801-goog
>
regards, Wolfgang
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