[PATCH v2 5/6] mailbox: Add generic mechanism for testing Mailbox Controllers
Jassi Brar
jassisinghbrar at gmail.com
Sun Aug 9 23:45:33 PDT 2015
On Mon, Jul 27, 2015 at 3:14 PM, Lee Jones <lee.jones at linaro.org> wrote:
> This particular Client implementation uses shared memory in order
> to pass messages between Mailbox users; however, it can be easily
> hacked to support any type of Controller.
>
> Signed-off-by: Lee Jones <lee.jones at linaro.org>
> ---
> drivers/mailbox/Kconfig | 7 ++
> drivers/mailbox/Makefile | 2 +
> drivers/mailbox/mailbox-test.c | 210 +++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 219 insertions(+)
> create mode 100644 drivers/mailbox/mailbox-test.c
>
> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
> index 2cc4c39..7720bde 100644
> --- a/drivers/mailbox/Kconfig
> +++ b/drivers/mailbox/Kconfig
> @@ -77,4 +77,11 @@ config STI_MBOX
> Mailbox implementation for STMicroelectonics family chips with
> hardware for interprocessor communication.
>
> +config MAILBOX_TEST
> + tristate "Mailbox Test Client"
> + depends on OF
> + help
> + Test client to help with testing new Controller driver
> + implementations.
> +
> endif
> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
> index 7cb4766..92435ef 100644
> --- a/drivers/mailbox/Makefile
> +++ b/drivers/mailbox/Makefile
> @@ -2,6 +2,8 @@
>
> obj-$(CONFIG_MAILBOX) += mailbox.o
>
> +obj-$(CONFIG_MAILBOX_TEST) += mailbox-test.o
> +
> obj-$(CONFIG_ARM_MHU) += arm_mhu.o
>
> obj-$(CONFIG_PL320_MBOX) += pl320-ipc.o
> diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c
> new file mode 100644
> index 0000000..10bfe3a
> --- /dev/null
> +++ b/drivers/mailbox/mailbox-test.c
> @@ -0,0 +1,210 @@
> +/*
> + * Copyright (C) 2015 ST Microelectronics
> + *
> + * Author: Lee Jones <lee.jones at linaro.org>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#include <linux/debugfs.h>
> +#include <linux/err.h>
> +#include <linux/kernel.h>
> +#include <linux/mailbox_client.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/uaccess.h>
> +
> +#define MBOX_MAX_MSG_LEN 128
> +
> +static struct dentry *root_debugfs_dir;
> +
> +struct mbox_test_device {
> + struct device *dev;
> + struct mbox_chan *tx_channel;
> + struct mbox_chan *rx_channel;
> + void __iomem *mmio;
> +
> +};
> +
> +static ssize_t mbox_test_write(struct file *filp,
> + const char __user *userbuf,
> + size_t count, loff_t *ppos)
> +{
> + struct mbox_test_device *tdev = filp->private_data;
> + char *message;
> + int ret;
> +
> + if (count > MBOX_MAX_MSG_LEN) {
> + dev_err(tdev->dev,
> + "Message length %d greater than max allowed %d\n",
> + count, MBOX_MAX_MSG_LEN);
> + return -EINVAL;
> + }
> +
> + message = kzalloc(count, GFP_KERNEL);
> + if (!message)
> + return -ENOMEM;
> +
> + ret = copy_from_user(message, userbuf, count);
> + if (ret)
> + return -EFAULT;
> +
> + print_hex_dump(KERN_ERR, "Client: Sending: ", DUMP_PREFIX_ADDRESS,
> + 16, 1, message, 16, true);
> +
> + ret = mbox_send_message(tdev->tx_channel, message);
> + if (ret < 0)
> + dev_err(tdev->dev, "Failed to send message via mailbox\n");
> +
> + kfree(message);
> +
> + return ret < 0 ? ret : count;
> +}
> +
> +static const struct file_operations mbox_test_ops = {
> + .write = mbox_test_write,
> + .open = simple_open,
> + .llseek = generic_file_llseek,
> +};
> +
> +static int mbox_test_add_debugfs(struct platform_device *pdev,
> + struct mbox_test_device *tdev)
> +{
> + if (!debugfs_initialized())
> + return 0;
> +
> + root_debugfs_dir = debugfs_create_dir("mailbox", NULL);
> + if (!root_debugfs_dir) {
> + dev_err(&pdev->dev, "Failed to create Mailbox debugfs\n");
> + return -EINVAL;
> + }
> +
> + debugfs_create_file("send-message", 0200, root_debugfs_dir,
> + tdev, &mbox_test_ops);
> +
> + return 0;
> +}
> +
> +static void mbox_test_receive_message(struct mbox_client *client, void *message)
> +{
> + struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
> +
> + if (!tdev->mmio) {
> + dev_info(tdev->dev, "Client: Recived something [read mmio]\n");
> + return;
> + }
> +
> + print_hex_dump(KERN_ERR, "Client: from co-proc: ", DUMP_PREFIX_ADDRESS,
> + 16, 1, tdev->mmio, MBOX_MAX_MSG_LEN, true);
> +}
> +
> +static void mbox_test_prepare_message(struct mbox_client *client, void *message)
> +{
> + struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
> +
> + if (tdev->mmio)
> + memcpy(tdev->mmio, message, MBOX_MAX_MSG_LEN);
>
This is unlikely to work. Those platforms that need to send a 2 part
message, they do :
(a) Signal/Command/Target code via some controller register (via
mbox_send_message).
(b) Setup the payload in Shared-Memory (via tx_prepare).
This test driver assumes both are the same. I think you have to
declare something like
struct mbox_test_message { /* same for TX and RX */
unsigned sig_len;
void *signal; /* rx/tx via mailbox api */
unsigned pl_len;
void *payload; /* rx/tx via shared-memory */
};
> +
> +static void mbox_test_message_sent(struct mbox_client *client,
> + void *message, int r)
> +{
> + if (r)
> + dev_warn(client->dev,
> + "Client: Message could not be sent: %d\n", r);
> + else
> + dev_info(client->dev,
> + "Client: Message sent\n");
> +}
> +
> +static struct mbox_chan *
> +mbox_test_request_channel(struct platform_device *pdev, const char *name)
> +{
> + struct mbox_client *client;
> +
> + client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL);
> + if (!client)
> + return ERR_PTR(-ENOMEM);
> +
> + client->dev = &pdev->dev;
> + client->rx_callback = mbox_test_receive_message;
> + client->tx_prepare = mbox_test_prepare_message;
> + client->tx_done = mbox_test_message_sent;
> + client->tx_block = true;
> + client->knows_txdone = false;
> + client->tx_tout = 500;
> +
> + return mbox_request_channel_byname(client, name);
> +}
> +
> +static int mbox_test_probe(struct platform_device *pdev)
> +{
> + struct mbox_test_device *tdev;
> + struct resource *res;
> + int ret;
> +
> + tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL);
> + if (!tdev)
> + return -ENOMEM;
> +
> + /* It's okay for MMIO to be NULL */
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + tdev->mmio = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(tdev->mmio))
> + tdev->mmio = NULL;
> +
> + tdev->tx_channel = mbox_test_request_channel(pdev, "tx");
> + if (IS_ERR(tdev->tx_channel))
> + return PTR_ERR(tdev->tx_channel);
> +
> + tdev->rx_channel = mbox_test_request_channel(pdev, "rx");
> + if (IS_ERR(tdev->rx_channel))
> + return PTR_ERR(tdev->rx_channel);
> +
Should it really fail on TX or RX only clients?
It takes write from userspace but shouldn't it also provide data
received to the userspace?
Cheers.
Jassi
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