[PATCH v2 3/5] soc: add polarfire soc system controller
Ben Dooks
ben.dooks at codethink.co.uk
Tue Dec 1 07:29:29 EST 2020
On 01/12/2020 12:21, Damien Le Moal wrote:
> On 2020/12/01 21:18, Ben Dooks wrote:
>> On 01/12/2020 12:00, Damien Le Moal wrote:
>>> On 2020/12/01 20:03, conor.dooley at microchip.com wrote:
>>>> From: Conor Dooley <conor.dooley at microchip.com>
>>>>
>>>> This driver provides an interface for other drivers to access the
>>>> functions of the system controller on the Microchip PolarFire SoC.
>>>>
>>>> Signed-off-by: Conor Dooley <conor.dooley at microchip.com>
>>>> ---
>>>> drivers/soc/Kconfig | 1 +
>>>> drivers/soc/Makefile | 1 +
>>>> drivers/soc/microchip/Kconfig | 10 ++
>>>> drivers/soc/microchip/Makefile | 1 +
>>>> drivers/soc/microchip/mpfs_sys_controller.c | 135 ++++++++++++++++++++
>>>> 5 files changed, 148 insertions(+)
>>>> create mode 100644 drivers/soc/microchip/Kconfig
>>>> create mode 100644 drivers/soc/microchip/Makefile
>>>> create mode 100644 drivers/soc/microchip/mpfs_sys_controller.c
>>>>
>>>> diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
>>>> index 425ab6f7e375..22cb097bcbdc 100644
>>>> --- a/drivers/soc/Kconfig
>>>> +++ b/drivers/soc/Kconfig
>>>> @@ -9,6 +9,7 @@ source "drivers/soc/bcm/Kconfig"
>>>> source "drivers/soc/fsl/Kconfig"
>>>> source "drivers/soc/imx/Kconfig"
>>>> source "drivers/soc/ixp4xx/Kconfig"
>>>> +source "drivers/soc/microchip/Kconfig"
>>>> source "drivers/soc/mediatek/Kconfig"
>>>> source "drivers/soc/qcom/Kconfig"
>>>> source "drivers/soc/renesas/Kconfig"
>>>> diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
>>>> index 36452bed86ef..fb084cf2d12e 100644
>>>> --- a/drivers/soc/Makefile
>>>> +++ b/drivers/soc/Makefile
>>>> @@ -14,6 +14,7 @@ obj-$(CONFIG_ARCH_GEMINI) += gemini/
>>>> obj-y += imx/
>>>> obj-$(CONFIG_ARCH_IXP4XX) += ixp4xx/
>>>> obj-$(CONFIG_SOC_XWAY) += lantiq/
>>>> +obj-$(CONFIG_SOC_MICROCHIP_POLARFIRE) += microchip/
>>>> obj-y += mediatek/
>>>> obj-y += amlogic/
>>>> obj-y += qcom/
>>>> diff --git a/drivers/soc/microchip/Kconfig b/drivers/soc/microchip/Kconfig
>>>> new file mode 100644
>>>> index 000000000000..40e5203c8ba0
>>>> --- /dev/null
>>>> +++ b/drivers/soc/microchip/Kconfig
>>>> @@ -0,0 +1,10 @@
>>>> +config MPFS_SYS_CONTROLLER
>>>> + tristate "MPFS_SYS_CONTROLLER"
>>>> + depends on MPFS_MBOX
>>>> + help
>>>> + This driver adds support for the Polarfire SoC system controller.
>>>> +
>>>> + To compile this driver as a module, choose M here. the
>>>> + module will be called mpfs_system_controller.
>>>> +
>>>> + If unsure, say N.
>>>> diff --git a/drivers/soc/microchip/Makefile b/drivers/soc/microchip/Makefile
>>>> new file mode 100644
>>>> index 000000000000..23b1f42a37db
>>>> --- /dev/null
>>>> +++ b/drivers/soc/microchip/Makefile
>>>> @@ -0,0 +1 @@
>>>> +obj-$(CONFIG_MPFS_SYS_CONTROLLER) += mpfs_sys_controller.o
>>>> diff --git a/drivers/soc/microchip/mpfs_sys_controller.c b/drivers/soc/microchip/mpfs_sys_controller.c
>>>> new file mode 100644
>>>> index 000000000000..875a0671e196
>>>> --- /dev/null
>>>> +++ b/drivers/soc/microchip/mpfs_sys_controller.c
>>>> @@ -0,0 +1,135 @@
>>>> +// SPDX-License-Identifier: GPL-2.0
>>>> +/*
>>>> + * Microchip MPFS system controller driver
>>>> + *
>>>> + * Copyright (c) 2020 Microchip Corporation. All rights reserved.
>>>> + *
>>>> + * Author: Conor Dooley <conor.dooley at microchip.com>
>>>> + *
>>>> + */
>>>> +
>>>> +#include <linux/slab.h>
>>>> +#include <linux/module.h>
>>>> +#include <linux/interrupt.h>
>>>> +#include <linux/of_platform.h>
>>>> +#include <linux/mailbox_client.h>
>>>> +#include <linux/platform_device.h>
>>>> +#include <soc/microchip/mpfs.h>
>>>> +
>>>> +static DEFINE_MUTEX(transaction_lock);
>>>> +
>>>> +struct mpfs_sys_controller {
>>>> + struct mbox_client client;
>>>> + struct mbox_chan *chan;
>>>> + struct completion c;
>>>> + u32 enabled;
>>>> + void *response;
>>>> + u16 response_size_bytes;
>>>> +};
>>>> +
>>>> +int mpfs_blocking_transaction(struct mpfs_sys_controller *mpfs_client, void *msg,
>>>> + void *response, u16 response_size_bytes)
>>>> +{
>>>> + int ret;
>>>> +
>>>> + mpfs_client->response = response;
>>>> + mpfs_client->response_size_bytes = response_size_bytes;
>>>> +
>>>> + mutex_lock_interruptible(&transaction_lock);
>>>> +
>>>> + reinit_completion(&mpfs_client->c);
>>>> +
>>>> + ret = mbox_send_message(mpfs_client->chan, msg);
>>>> + if (ret >= 0) {
>>>> + if (wait_for_completion_timeout(&mpfs_client->c, HZ)) {
>>>> + ret = 0;
>>>> + } else {
>>>> + ret = -ETIMEDOUT;
>>>> + dev_warn(mpfs_client->client.dev, "MPFS sys controller transaction timeout");
>>>> + }
>>>> + } else {
>>>> + dev_err(mpfs_client->client.dev,
>>>> + "mpfs sys controller transaction returned %d\r\n", ret);
>>>> + }
>>>> +
>>>> + mutex_unlock(&transaction_lock);
>>>> +
>>>> + return ret;
>>>> +}
>>>> +EXPORT_SYMBOL(mpfs_blocking_transaction);
>>>> +
>>>> +static void rx_callback(struct mbox_client *client, void *msg)
>>>> +{
>>>> + struct mpfs_sys_controller *mpfs_client =
>>>> + container_of(client, struct mpfs_sys_controller, client);
>>>> +
>>>> + memcpy(mpfs_client->response, (u8 *)msg,
>>>> + mpfs_client->response_size_bytes);
>>>> +
>>>> + complete(&mpfs_client->c);
>>>> +}
>>>> +
>>>> +static int mpfs_sys_controller_probe(struct platform_device *pdev)
>>>> +{
>>>> + struct device *dev = &pdev->dev;
>>>> + struct mpfs_sys_controller *mpfs_client;
>>>> +
>>>> + mpfs_client = devm_kzalloc(dev, sizeof(*mpfs_client), GFP_KERNEL);
>>>> + if (!mpfs_client)
>>>> + return -ENOMEM;
>>>> +
>>>> + mpfs_client->client.dev = dev;
>>>> + mpfs_client->client.rx_callback = rx_callback;
>>>> + mpfs_client->client.tx_block = 1U;
>>>> +
>>>> + mpfs_client->chan = mbox_request_channel_byname(&mpfs_client->client,
>>>> + "mbox-mpfs");
>>>> + if (IS_ERR(mpfs_client->chan)) {
>>>> + int ret = PTR_ERR(mpfs_client->chan);
>>>> +
>>>> + if (ret != -EPROBE_DEFER)
>>>> + dev_err(dev, "Failed to get mbox channel: %d\n", ret);
>>>> + return ret;
>>>
>>> You can replace all of this with
>>>
>>> return dev_err_probe(dev, PTR_ERR(mpfs_client->chan),
>>> ""Failed to get mbox channel\n");
>>
>> you'll spam the error log if you get a lot of probe defferals.
>> I think the code as is fine.
>
> Please look at that function code: it does not print anything if the error is
> -EPROBE_DEFER.
>
ah, ok.
--
Ben Dooks http://www.codethink.co.uk/
Senior Engineer Codethink - Providing Genius
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