Re: [PATCH 4/5] mailbox: apple: Delete driver

From: Eric Curtin
Date: Tue Mar 28 2023 - 09:38:19 EST


On Tue, 28 Mar 2023 at 14:21, Hector Martin <marcan@xxxxxxxxx> wrote:
>
> This driver is now orphaned and superseded by
> drivers/soc/apple/mailbox.c.
>
> Signed-off-by: Hector Martin <marcan@xxxxxxxxx>

Watched the stream

Acked-by: Eric Curtin <ecurtin@xxxxxxxxxx>

Is mise le meas/Regards,

Eric Curtin

> ---
> MAINTAINERS | 2 -
> drivers/mailbox/Kconfig | 12 --
> drivers/mailbox/Makefile | 2 -
> drivers/mailbox/apple-mailbox.c | 441 ----------------------------------------
> include/linux/apple-mailbox.h | 19 --
> 5 files changed, 476 deletions(-)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 8d5bc223f305..c115e0ad41da 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1966,7 +1966,6 @@ F: drivers/i2c/busses/i2c-pasemi-platform.c
> F: drivers/iommu/apple-dart.c
> F: drivers/iommu/io-pgtable-dart.c
> F: drivers/irqchip/irq-apple-aic.c
> -F: drivers/mailbox/apple-mailbox.c
> F: drivers/nvme/host/apple.c
> F: drivers/nvmem/apple-efuses.c
> F: drivers/pinctrl/pinctrl-apple-gpio.c
> @@ -1974,7 +1973,6 @@ F: drivers/soc/apple/*
> F: drivers/watchdog/apple_wdt.c
> F: include/dt-bindings/interrupt-controller/apple-aic.h
> F: include/dt-bindings/pinctrl/apple.h
> -F: include/linux/apple-mailbox.h
> F: include/linux/soc/apple/*
>
> ARM/APPLE MACHINE SOUND DRIVERS
> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
> index 1495965bc394..73952108cc52 100644
> --- a/drivers/mailbox/Kconfig
> +++ b/drivers/mailbox/Kconfig
> @@ -8,18 +8,6 @@ menuconfig MAILBOX
>
> if MAILBOX
>
> -config APPLE_MAILBOX
> - tristate "Apple Mailbox driver"
> - depends on ARCH_APPLE || (ARM64 && COMPILE_TEST)
> - default ARCH_APPLE
> - help
> - Apple SoCs have various co-processors required for certain
> - peripherals to work (NVMe, display controller, etc.). This
> - driver adds support for the mailbox controller used to
> - communicate with those.
> -
> - Say Y here if you have a Apple SoC.
> -
> config ARM_MHU
> tristate "ARM MHU Mailbox"
> depends on ARM_AMBA
> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
> index fc9376117111..18793e6caa2f 100644
> --- a/drivers/mailbox/Makefile
> +++ b/drivers/mailbox/Makefile
> @@ -60,5 +60,3 @@ obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o
> obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o
>
> obj-$(CONFIG_QCOM_IPCC) += qcom-ipcc.o
> -
> -obj-$(CONFIG_APPLE_MAILBOX) += apple-mailbox.o
> diff --git a/drivers/mailbox/apple-mailbox.c b/drivers/mailbox/apple-mailbox.c
> deleted file mode 100644
> index 2a3e8d8ff8b5..000000000000
> --- a/drivers/mailbox/apple-mailbox.c
> +++ /dev/null
> @@ -1,441 +0,0 @@
> -// SPDX-License-Identifier: GPL-2.0-only OR MIT
> -/*
> - * Apple mailbox driver
> - *
> - * Copyright (C) 2021 The Asahi Linux Contributors
> - *
> - * This driver adds support for two mailbox variants (called ASC and M3 by
> - * Apple) found in Apple SoCs such as the M1. It consists of two FIFOs used to
> - * exchange 64+32 bit messages between the main CPU and a co-processor.
> - * Various coprocessors implement different IPC protocols based on these simple
> - * messages and shared memory buffers.
> - *
> - * Both the main CPU and the co-processor see the same set of registers but
> - * the first FIFO (A2I) is always used to transfer messages from the application
> - * processor (us) to the I/O processor and the second one (I2A) for the
> - * other direction.
> - */
> -
> -#include <linux/apple-mailbox.h>
> -#include <linux/delay.h>
> -#include <linux/device.h>
> -#include <linux/gfp.h>
> -#include <linux/interrupt.h>
> -#include <linux/io.h>
> -#include <linux/mailbox_controller.h>
> -#include <linux/module.h>
> -#include <linux/of.h>
> -#include <linux/platform_device.h>
> -#include <linux/spinlock.h>
> -#include <linux/types.h>
> -
> -#define APPLE_ASC_MBOX_CONTROL_FULL BIT(16)
> -#define APPLE_ASC_MBOX_CONTROL_EMPTY BIT(17)
> -
> -#define APPLE_ASC_MBOX_A2I_CONTROL 0x110
> -#define APPLE_ASC_MBOX_A2I_SEND0 0x800
> -#define APPLE_ASC_MBOX_A2I_SEND1 0x808
> -#define APPLE_ASC_MBOX_A2I_RECV0 0x810
> -#define APPLE_ASC_MBOX_A2I_RECV1 0x818
> -
> -#define APPLE_ASC_MBOX_I2A_CONTROL 0x114
> -#define APPLE_ASC_MBOX_I2A_SEND0 0x820
> -#define APPLE_ASC_MBOX_I2A_SEND1 0x828
> -#define APPLE_ASC_MBOX_I2A_RECV0 0x830
> -#define APPLE_ASC_MBOX_I2A_RECV1 0x838
> -
> -#define APPLE_M3_MBOX_CONTROL_FULL BIT(16)
> -#define APPLE_M3_MBOX_CONTROL_EMPTY BIT(17)
> -
> -#define APPLE_M3_MBOX_A2I_CONTROL 0x50
> -#define APPLE_M3_MBOX_A2I_SEND0 0x60
> -#define APPLE_M3_MBOX_A2I_SEND1 0x68
> -#define APPLE_M3_MBOX_A2I_RECV0 0x70
> -#define APPLE_M3_MBOX_A2I_RECV1 0x78
> -
> -#define APPLE_M3_MBOX_I2A_CONTROL 0x80
> -#define APPLE_M3_MBOX_I2A_SEND0 0x90
> -#define APPLE_M3_MBOX_I2A_SEND1 0x98
> -#define APPLE_M3_MBOX_I2A_RECV0 0xa0
> -#define APPLE_M3_MBOX_I2A_RECV1 0xa8
> -
> -#define APPLE_M3_MBOX_IRQ_ENABLE 0x48
> -#define APPLE_M3_MBOX_IRQ_ACK 0x4c
> -#define APPLE_M3_MBOX_IRQ_A2I_EMPTY BIT(0)
> -#define APPLE_M3_MBOX_IRQ_A2I_NOT_EMPTY BIT(1)
> -#define APPLE_M3_MBOX_IRQ_I2A_EMPTY BIT(2)
> -#define APPLE_M3_MBOX_IRQ_I2A_NOT_EMPTY BIT(3)
> -
> -#define APPLE_MBOX_MSG1_OUTCNT GENMASK(56, 52)
> -#define APPLE_MBOX_MSG1_INCNT GENMASK(51, 48)
> -#define APPLE_MBOX_MSG1_OUTPTR GENMASK(47, 44)
> -#define APPLE_MBOX_MSG1_INPTR GENMASK(43, 40)
> -#define APPLE_MBOX_MSG1_MSG GENMASK(31, 0)
> -
> -struct apple_mbox_hw {
> - unsigned int control_full;
> - unsigned int control_empty;
> -
> - unsigned int a2i_control;
> - unsigned int a2i_send0;
> - unsigned int a2i_send1;
> -
> - unsigned int i2a_control;
> - unsigned int i2a_recv0;
> - unsigned int i2a_recv1;
> -
> - bool has_irq_controls;
> - unsigned int irq_enable;
> - unsigned int irq_ack;
> - unsigned int irq_bit_recv_not_empty;
> - unsigned int irq_bit_send_empty;
> -};
> -
> -struct apple_mbox {
> - void __iomem *regs;
> - const struct apple_mbox_hw *hw;
> -
> - int irq_recv_not_empty;
> - int irq_send_empty;
> -
> - struct mbox_chan chan;
> -
> - struct device *dev;
> - struct mbox_controller controller;
> - spinlock_t rx_lock;
> -};
> -
> -static const struct of_device_id apple_mbox_of_match[];
> -
> -static bool apple_mbox_hw_can_send(struct apple_mbox *apple_mbox)
> -{
> - u32 mbox_ctrl =
> - readl_relaxed(apple_mbox->regs + apple_mbox->hw->a2i_control);
> -
> - return !(mbox_ctrl & apple_mbox->hw->control_full);
> -}
> -
> -static bool apple_mbox_hw_send_empty(struct apple_mbox *apple_mbox)
> -{
> - u32 mbox_ctrl =
> - readl_relaxed(apple_mbox->regs + apple_mbox->hw->a2i_control);
> -
> - return mbox_ctrl & apple_mbox->hw->control_empty;
> -}
> -
> -static int apple_mbox_hw_send(struct apple_mbox *apple_mbox,
> - struct apple_mbox_msg *msg)
> -{
> - if (!apple_mbox_hw_can_send(apple_mbox))
> - return -EBUSY;
> -
> - dev_dbg(apple_mbox->dev, "> TX %016llx %08x\n", msg->msg0, msg->msg1);
> -
> - writeq_relaxed(msg->msg0, apple_mbox->regs + apple_mbox->hw->a2i_send0);
> - writeq_relaxed(FIELD_PREP(APPLE_MBOX_MSG1_MSG, msg->msg1),
> - apple_mbox->regs + apple_mbox->hw->a2i_send1);
> -
> - return 0;
> -}
> -
> -static bool apple_mbox_hw_can_recv(struct apple_mbox *apple_mbox)
> -{
> - u32 mbox_ctrl =
> - readl_relaxed(apple_mbox->regs + apple_mbox->hw->i2a_control);
> -
> - return !(mbox_ctrl & apple_mbox->hw->control_empty);
> -}
> -
> -static int apple_mbox_hw_recv(struct apple_mbox *apple_mbox,
> - struct apple_mbox_msg *msg)
> -{
> - if (!apple_mbox_hw_can_recv(apple_mbox))
> - return -ENOMSG;
> -
> - msg->msg0 = readq_relaxed(apple_mbox->regs + apple_mbox->hw->i2a_recv0);
> - msg->msg1 = FIELD_GET(
> - APPLE_MBOX_MSG1_MSG,
> - readq_relaxed(apple_mbox->regs + apple_mbox->hw->i2a_recv1));
> -
> - dev_dbg(apple_mbox->dev, "< RX %016llx %08x\n", msg->msg0, msg->msg1);
> -
> - return 0;
> -}
> -
> -static int apple_mbox_chan_send_data(struct mbox_chan *chan, void *data)
> -{
> - struct apple_mbox *apple_mbox = chan->con_priv;
> - struct apple_mbox_msg *msg = data;
> - int ret;
> -
> - ret = apple_mbox_hw_send(apple_mbox, msg);
> - if (ret)
> - return ret;
> -
> - /*
> - * The interrupt is level triggered and will keep firing as long as the
> - * FIFO is empty. It will also keep firing if the FIFO was empty
> - * at any point in the past until it has been acknowledged at the
> - * mailbox level. By acknowledging it here we can ensure that we will
> - * only get the interrupt once the FIFO has been cleared again.
> - * If the FIFO is already empty before the ack it will fire again
> - * immediately after the ack.
> - */
> - if (apple_mbox->hw->has_irq_controls) {
> - writel_relaxed(apple_mbox->hw->irq_bit_send_empty,
> - apple_mbox->regs + apple_mbox->hw->irq_ack);
> - }
> - enable_irq(apple_mbox->irq_send_empty);
> -
> - return 0;
> -}
> -
> -static irqreturn_t apple_mbox_send_empty_irq(int irq, void *data)
> -{
> - struct apple_mbox *apple_mbox = data;
> -
> - /*
> - * We don't need to acknowledge the interrupt at the mailbox level
> - * here even if supported by the hardware. It will keep firing but that
> - * doesn't matter since it's disabled at the main interrupt controller.
> - * apple_mbox_chan_send_data will acknowledge it before enabling
> - * it at the main controller again.
> - */
> - disable_irq_nosync(apple_mbox->irq_send_empty);
> - mbox_chan_txdone(&apple_mbox->chan, 0);
> - return IRQ_HANDLED;
> -}
> -
> -static int apple_mbox_poll(struct apple_mbox *apple_mbox)
> -{
> - struct apple_mbox_msg msg;
> - int ret = 0;
> -
> - while (apple_mbox_hw_recv(apple_mbox, &msg) == 0) {
> - mbox_chan_received_data(&apple_mbox->chan, (void *)&msg);
> - ret++;
> - }
> -
> - /*
> - * The interrupt will keep firing even if there are no more messages
> - * unless we also acknowledge it at the mailbox level here.
> - * There's no race if a message comes in between the check in the while
> - * loop above and the ack below: If a new messages arrives inbetween
> - * those two the interrupt will just fire again immediately after the
> - * ack since it's level triggered.
> - */
> - if (apple_mbox->hw->has_irq_controls) {
> - writel_relaxed(apple_mbox->hw->irq_bit_recv_not_empty,
> - apple_mbox->regs + apple_mbox->hw->irq_ack);
> - }
> -
> - return ret;
> -}
> -
> -static irqreturn_t apple_mbox_recv_irq(int irq, void *data)
> -{
> - struct apple_mbox *apple_mbox = data;
> -
> - spin_lock(&apple_mbox->rx_lock);
> - apple_mbox_poll(apple_mbox);
> - spin_unlock(&apple_mbox->rx_lock);
> -
> - return IRQ_HANDLED;
> -}
> -
> -static bool apple_mbox_chan_peek_data(struct mbox_chan *chan)
> -{
> - struct apple_mbox *apple_mbox = chan->con_priv;
> - unsigned long flags;
> - int ret;
> -
> - spin_lock_irqsave(&apple_mbox->rx_lock, flags);
> - ret = apple_mbox_poll(apple_mbox);
> - spin_unlock_irqrestore(&apple_mbox->rx_lock, flags);
> -
> - return ret > 0;
> -}
> -
> -static int apple_mbox_chan_flush(struct mbox_chan *chan, unsigned long timeout)
> -{
> - struct apple_mbox *apple_mbox = chan->con_priv;
> - unsigned long deadline = jiffies + msecs_to_jiffies(timeout);
> -
> - while (time_before(jiffies, deadline)) {
> - if (apple_mbox_hw_send_empty(apple_mbox)) {
> - mbox_chan_txdone(&apple_mbox->chan, 0);
> - return 0;
> - }
> -
> - udelay(1);
> - }
> -
> - return -ETIME;
> -}
> -
> -static int apple_mbox_chan_startup(struct mbox_chan *chan)
> -{
> - struct apple_mbox *apple_mbox = chan->con_priv;
> -
> - /*
> - * Only some variants of this mailbox HW provide interrupt control
> - * at the mailbox level. We therefore need to handle enabling/disabling
> - * interrupts at the main interrupt controller anyway for hardware that
> - * doesn't. Just always keep the interrupts we care about enabled at
> - * the mailbox level so that both hardware revisions behave almost
> - * the same.
> - */
> - if (apple_mbox->hw->has_irq_controls) {
> - writel_relaxed(apple_mbox->hw->irq_bit_recv_not_empty |
> - apple_mbox->hw->irq_bit_send_empty,
> - apple_mbox->regs + apple_mbox->hw->irq_enable);
> - }
> -
> - enable_irq(apple_mbox->irq_recv_not_empty);
> - return 0;
> -}
> -
> -static void apple_mbox_chan_shutdown(struct mbox_chan *chan)
> -{
> - struct apple_mbox *apple_mbox = chan->con_priv;
> -
> - disable_irq(apple_mbox->irq_recv_not_empty);
> -}
> -
> -static const struct mbox_chan_ops apple_mbox_ops = {
> - .send_data = apple_mbox_chan_send_data,
> - .peek_data = apple_mbox_chan_peek_data,
> - .flush = apple_mbox_chan_flush,
> - .startup = apple_mbox_chan_startup,
> - .shutdown = apple_mbox_chan_shutdown,
> -};
> -
> -static struct mbox_chan *apple_mbox_of_xlate(struct mbox_controller *mbox,
> - const struct of_phandle_args *args)
> -{
> - if (args->args_count != 0)
> - return ERR_PTR(-EINVAL);
> -
> - return &mbox->chans[0];
> -}
> -
> -static int apple_mbox_probe(struct platform_device *pdev)
> -{
> - int ret;
> - const struct of_device_id *match;
> - char *irqname;
> - struct apple_mbox *mbox;
> - struct device *dev = &pdev->dev;
> -
> - match = of_match_node(apple_mbox_of_match, pdev->dev.of_node);
> - if (!match)
> - return -EINVAL;
> - if (!match->data)
> - return -EINVAL;
> -
> - mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL);
> - if (!mbox)
> - return -ENOMEM;
> - platform_set_drvdata(pdev, mbox);
> -
> - mbox->dev = dev;
> - mbox->regs = devm_platform_ioremap_resource(pdev, 0);
> - if (IS_ERR(mbox->regs))
> - return PTR_ERR(mbox->regs);
> -
> - mbox->hw = match->data;
> - mbox->irq_recv_not_empty =
> - platform_get_irq_byname(pdev, "recv-not-empty");
> - if (mbox->irq_recv_not_empty < 0)
> - return -ENODEV;
> -
> - mbox->irq_send_empty = platform_get_irq_byname(pdev, "send-empty");
> - if (mbox->irq_send_empty < 0)
> - return -ENODEV;
> -
> - mbox->controller.dev = mbox->dev;
> - mbox->controller.num_chans = 1;
> - mbox->controller.chans = &mbox->chan;
> - mbox->controller.ops = &apple_mbox_ops;
> - mbox->controller.txdone_irq = true;
> - mbox->controller.of_xlate = apple_mbox_of_xlate;
> - mbox->chan.con_priv = mbox;
> - spin_lock_init(&mbox->rx_lock);
> -
> - irqname = devm_kasprintf(dev, GFP_KERNEL, "%s-recv", dev_name(dev));
> - if (!irqname)
> - return -ENOMEM;
> -
> - ret = devm_request_threaded_irq(dev, mbox->irq_recv_not_empty, NULL,
> - apple_mbox_recv_irq,
> - IRQF_NO_AUTOEN | IRQF_ONESHOT, irqname,
> - mbox);
> - if (ret)
> - return ret;
> -
> - irqname = devm_kasprintf(dev, GFP_KERNEL, "%s-send", dev_name(dev));
> - if (!irqname)
> - return -ENOMEM;
> -
> - ret = devm_request_irq(dev, mbox->irq_send_empty,
> - apple_mbox_send_empty_irq, IRQF_NO_AUTOEN,
> - irqname, mbox);
> - if (ret)
> - return ret;
> -
> - return devm_mbox_controller_register(dev, &mbox->controller);
> -}
> -
> -static const struct apple_mbox_hw apple_mbox_asc_hw = {
> - .control_full = APPLE_ASC_MBOX_CONTROL_FULL,
> - .control_empty = APPLE_ASC_MBOX_CONTROL_EMPTY,
> -
> - .a2i_control = APPLE_ASC_MBOX_A2I_CONTROL,
> - .a2i_send0 = APPLE_ASC_MBOX_A2I_SEND0,
> - .a2i_send1 = APPLE_ASC_MBOX_A2I_SEND1,
> -
> - .i2a_control = APPLE_ASC_MBOX_I2A_CONTROL,
> - .i2a_recv0 = APPLE_ASC_MBOX_I2A_RECV0,
> - .i2a_recv1 = APPLE_ASC_MBOX_I2A_RECV1,
> -
> - .has_irq_controls = false,
> -};
> -
> -static const struct apple_mbox_hw apple_mbox_m3_hw = {
> - .control_full = APPLE_M3_MBOX_CONTROL_FULL,
> - .control_empty = APPLE_M3_MBOX_CONTROL_EMPTY,
> -
> - .a2i_control = APPLE_M3_MBOX_A2I_CONTROL,
> - .a2i_send0 = APPLE_M3_MBOX_A2I_SEND0,
> - .a2i_send1 = APPLE_M3_MBOX_A2I_SEND1,
> -
> - .i2a_control = APPLE_M3_MBOX_I2A_CONTROL,
> - .i2a_recv0 = APPLE_M3_MBOX_I2A_RECV0,
> - .i2a_recv1 = APPLE_M3_MBOX_I2A_RECV1,
> -
> - .has_irq_controls = true,
> - .irq_enable = APPLE_M3_MBOX_IRQ_ENABLE,
> - .irq_ack = APPLE_M3_MBOX_IRQ_ACK,
> - .irq_bit_recv_not_empty = APPLE_M3_MBOX_IRQ_I2A_NOT_EMPTY,
> - .irq_bit_send_empty = APPLE_M3_MBOX_IRQ_A2I_EMPTY,
> -};
> -
> -static const struct of_device_id apple_mbox_of_match[] = {
> - { .compatible = "apple,asc-mailbox-v4", .data = &apple_mbox_asc_hw },
> - { .compatible = "apple,m3-mailbox-v2", .data = &apple_mbox_m3_hw },
> - {}
> -};
> -MODULE_DEVICE_TABLE(of, apple_mbox_of_match);
> -
> -static struct platform_driver apple_mbox_driver = {
> - .driver = {
> - .name = "apple-mailbox",
> - .of_match_table = apple_mbox_of_match,
> - },
> - .probe = apple_mbox_probe,
> -};
> -module_platform_driver(apple_mbox_driver);
> -
> -MODULE_LICENSE("Dual MIT/GPL");
> -MODULE_AUTHOR("Sven Peter <sven@xxxxxxxxxxxxx>");
> -MODULE_DESCRIPTION("Apple Mailbox driver");
> diff --git a/include/linux/apple-mailbox.h b/include/linux/apple-mailbox.h
> deleted file mode 100644
> index 720fbb70294a..000000000000
> --- a/include/linux/apple-mailbox.h
> +++ /dev/null
> @@ -1,19 +0,0 @@
> -/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
> -/*
> - * Apple mailbox message format
> - *
> - * Copyright (C) 2021 The Asahi Linux Contributors
> - */
> -
> -#ifndef _LINUX_APPLE_MAILBOX_H_
> -#define _LINUX_APPLE_MAILBOX_H_
> -
> -#include <linux/types.h>
> -
> -/* encodes a single 96bit message sent over the single channel */
> -struct apple_mbox_msg {
> - u64 msg0;
> - u32 msg1;
> -};
> -
> -#endif
>
> --
> 2.40.0
>
>