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@xxxxxxxxxxxxx wrote:
From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
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@xxxxxxxxxxxxx>
---
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@xxxxxxxxxxxxx>
+ *
+ */
+
+#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
https://www.codethink.co.uk/privacy.html
