diff mbox

[V2,1/4] mailbox: add support for APM X-Gene platform mailbox driver

Message ID 1429741125-29156-2-git-send-email-fkan@apm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Feng Kan April 22, 2015, 10:18 p.m. UTC
Add support for APM X-Gene platform mailbox driver.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 drivers/mailbox/Kconfig                 |  10 ++
 drivers/mailbox/Makefile                |   2 +
 drivers/mailbox/mailbox-xgene-slimpro.c | 261 ++++++++++++++++++++++++++++++++
 3 files changed, 273 insertions(+)
 create mode 100644 drivers/mailbox/mailbox-xgene-slimpro.c

Comments

Paul Bolle April 24, 2015, 8:25 a.m. UTC | #1
On Wed, 2015-04-22 at 15:18 -0700, Feng Kan wrote:
> --- /dev/null
> +++ b/drivers/mailbox/mailbox-xgene-slimpro.c

> +static struct platform_driver slimpro_mbox_driver = {
> +	.probe	= slimpro_mbox_probe,
> +	.remove = slimpro_mbox_remove,
> +	.driver	= {
> +		.name = "xgene-slimpro-mbox",
> +		.owner = THIS_MODULE,
> +		.of_match_table = of_match_ptr(slimpro_of_match),
> +	},
> +};
> +
> +static int __init slimpro_mbox_init(void)
> +{
> +	return platform_driver_register(&slimpro_mbox_driver);
> +}
> +
> +subsys_initcall(slimpro_mbox_init);

After a quick scan of this driver you'd expect something like
    static void __exit slimpro_mbox_exit(void)
    {
	platform_driver_unregister(&slimpro_mbox_driver);
    }
    module_exit(slimpro_mbox_exit);

too here. At least, I do. Is there some non-obvious (to me) reason this
driver can't be unloaded if it is built as a module?

> +MODULE_DESCRIPTION("APM X-Gene SLIMpro Mailbox Driver");
> +MODULE_LICENSE("GPL");

Thanks,


Paul Bolle
Duc Dang Nov. 9, 2015, 6:05 p.m. UTC | #2
APM X-Gene SoC has a mailbox controller that provides
communication mechanism for X-Gene Arm64 cores to communicate
with X-Gene SoC's Cortex M3 (SLIMpro) processor.

X-Gene mailbox controller provides 8 mailbox channels, with
each channel has a dedicated interrupt line.

Changes since v2:
        - Rebase Feng's patch set over v4.3-rc5
        - Remove uneccessary 'inline' in function definition
	- Use module_platform_driver instead of subsys_initcall
        - Minor coding stype clean up

Changes since v1:
        - Add ACPI support
        - Use defines for reg offset

 .../bindings/mailbox/xgene-slimpro-mailbox.txt     |  34 +++
 arch/arm64/boot/dts/apm/apm-storm.dtsi             |  14 ++
 drivers/mailbox/Kconfig                            |   9 +
 drivers/mailbox/Makefile                           |   2 +
 drivers/mailbox/mailbox-xgene-slimpro.c            | 264 +++++++++++++++++++++
 5 files changed, 323 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mailbox/xgene-slimpro-mailbox.txt
 create mode 100644 drivers/mailbox/mailbox-xgene-slimpro.c
Duc Dang Nov. 16, 2015, 7:22 p.m. UTC | #3
On Mon, Nov 9, 2015 at 10:05 AM, Duc Dang <dhdang@apm.com> wrote:
> APM X-Gene SoC has a mailbox controller that provides
> communication mechanism for X-Gene Arm64 cores to communicate
> with X-Gene SoC's Cortex M3 (SLIMpro) processor.
>
> X-Gene mailbox controller provides 8 mailbox channels, with
> each channel has a dedicated interrupt line.
>
> Changes since v2:
>         - Rebase Feng's patch set over v4.3-rc5
>         - Remove uneccessary 'inline' in function definition
>         - Use module_platform_driver instead of subsys_initcall
>         - Minor coding stype clean up
>
> Changes since v1:
>         - Add ACPI support
>         - Use defines for reg offset
>
>  .../bindings/mailbox/xgene-slimpro-mailbox.txt     |  34 +++
>  arch/arm64/boot/dts/apm/apm-storm.dtsi             |  14 ++
>  drivers/mailbox/Kconfig                            |   9 +
>  drivers/mailbox/Makefile                           |   2 +
>  drivers/mailbox/mailbox-xgene-slimpro.c            | 264 +++++++++++++++++++++
>  5 files changed, 323 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mailbox/xgene-slimpro-mailbox.txt
>  create mode 100644 drivers/mailbox/mailbox-xgene-slimpro.c
>

Hi Jassi, Paul,

Do you have any comment on this patch set?

> --
> 1.9.1
>
Regards,
Duc dang.
Paul Bolle Nov. 20, 2015, 10:39 a.m. UTC | #4
Hi Duc,

On ma, 2015-11-16 at 11:22 -0800, Duc Dang wrote:
> Hi Jassi, Paul,
> 
> Do you have any comment on this patch set?

Are you perhaps confusing me with another Paul?

(I think I made a minor comment or two on this series about half a year
ago. But I'm not the maintainer here and it's the maintainers verdict
that you're probably interested in mostly. So it's not clear to me why
you specifically ask for my comment.)

Thanks,


Paul Bolle
diff mbox

Patch

diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index 84b0a2d..64120cc 100644
--- a/drivers/mailbox/Kconfig
+++ b/drivers/mailbox/Kconfig
@@ -60,4 +60,14 @@  config ALTERA_MBOX
 	  An implementation of the Altera Mailbox soft core. It is used
 	  to send message between processors. Say Y here if you want to use the
 	  Altera mailbox support.
+
+config XGENE_SLIMPRO_MBOX
+	tristate "APM SoC X-Gene SLIMpro Mailbox Controller"
+	depends on ARCH_XGENE
+	help
+	  An implementation of the APM X-Gene Interprocessor Communication
+	  Mailbox (IPCM) between the ARM 64-bit cores and SLIMpro controller.
+	  It is used to send short messages between ARM64-bit cores and
+	  the SLIMpro Management Engine, primarily for PM. Say Y here if you
+	  want to use the APM X-Gene SLIMpro IPCM support.
 endif
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
index b18201e..1e0bed5 100644
--- a/drivers/mailbox/Makefile
+++ b/drivers/mailbox/Makefile
@@ -11,3 +11,5 @@  obj-$(CONFIG_OMAP2PLUS_MBOX)	+= omap-mailbox.o
 obj-$(CONFIG_PCC)		+= pcc.o
 
 obj-$(CONFIG_ALTERA_MBOX)	+= mailbox-altera.o
+
+obj-$(CONFIG_XGENE_SLIMPRO_MBOX) += mailbox-xgene-slimpro.o
diff --git a/drivers/mailbox/mailbox-xgene-slimpro.c b/drivers/mailbox/mailbox-xgene-slimpro.c
new file mode 100644
index 0000000..49370e5
--- /dev/null
+++ b/drivers/mailbox/mailbox-xgene-slimpro.c
@@ -0,0 +1,261 @@ 
+/*
+ * APM X-Gene SLIMpro MailBox Driver
+ *
+ * Copyright (c) 2014, Applied Micro Circuits Corporation
+ * Author: Feng Kan fkan@apm.com
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#include <linux/delay.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>
+
+#define MBOX_CON_NAME			"slimpro-mbox"
+#define MBOX_REG_SET_OFFSET		0x1000
+#define MBOX_CNT			8
+#define MBOX_STATUS_AVAIL_MASK		BIT(16)
+#define MBOX_STATUS_ACK_MASK		BIT(0)
+
+/* Configuration and Status Registers */
+#define REG_DB_IN		0x00
+#define REG_DB_DIN0		0x04
+#define REG_DB_DIN1		0x08
+#define REG_DB_OUT		0x10
+#define REG_DB_DOUT0		0x14
+#define REG_DB_DOUT1		0x18
+#define REG_DB_STAT		0x20
+#define REG_DB_STATMASK		0x24
+
+struct slimpro_mbox_chan {
+	struct device *dev;
+	struct mbox_chan *chan;
+	void __iomem *reg;
+	int id;
+	int irq;
+	u32 rx_msg[3];
+};
+
+struct slimpro_mbox {
+	struct mbox_controller mb_ctrl;
+	struct slimpro_mbox_chan mc[MBOX_CNT];
+	struct mbox_chan chans[MBOX_CNT];
+};
+
+static inline void mb_chan_send_msg(struct slimpro_mbox_chan *mb_chan, u32 *msg)
+{
+	writel(msg[1], mb_chan->reg + REG_DB_DOUT0);
+	writel(msg[2], mb_chan->reg + REG_DB_DOUT1);
+	writel(msg[0], mb_chan->reg + REG_DB_OUT);
+}
+
+static inline void mb_chan_recv_msg(struct slimpro_mbox_chan *mb_chan)
+{
+	mb_chan->rx_msg[1] = readl(mb_chan->reg + REG_DB_DIN0);
+	mb_chan->rx_msg[2] = readl(mb_chan->reg + REG_DB_DIN1);
+	mb_chan->rx_msg[0] = readl(mb_chan->reg + REG_DB_IN);
+}
+
+static void mb_chan_enable_int(struct slimpro_mbox_chan *mb_chan, u32 mask)
+{
+	u32 val = readl(mb_chan->reg + REG_DB_STATMASK);
+
+	val &= ~mask;
+
+	writel(val, mb_chan->reg + REG_DB_STATMASK);
+}
+
+static void mb_chan_disable_int(struct slimpro_mbox_chan *mb_chan, u32 mask)
+{
+	u32 val = readl(mb_chan->reg + REG_DB_STATMASK);
+
+	val |= mask;
+
+	writel(val, mb_chan->reg + REG_DB_STATMASK);
+}
+
+static int mb_chan_status_ack(struct slimpro_mbox_chan *mb_chan)
+{
+	u32 val = readl(mb_chan->reg + REG_DB_STAT);
+
+	if (val & MBOX_STATUS_ACK_MASK) {
+		writel(MBOX_STATUS_ACK_MASK, mb_chan->reg + REG_DB_STAT);
+		return 1;
+	}
+	return 0;
+}
+
+static int mb_chan_status_avail(struct slimpro_mbox_chan *mb_chan)
+{
+	u32 val = readl(mb_chan->reg + REG_DB_STAT);
+
+	if (val & MBOX_STATUS_AVAIL_MASK) {
+		mb_chan_recv_msg(mb_chan);
+		writel(MBOX_STATUS_AVAIL_MASK, mb_chan->reg + REG_DB_STAT);
+		return 1;
+	}
+	return 0;
+}
+
+static irqreturn_t slimpro_mbox_irq(int irq, void *id)
+{
+	struct slimpro_mbox_chan *mb_chan = id;
+
+	if (mb_chan_status_ack(mb_chan))
+		mbox_chan_txdone(mb_chan->chan, 0);
+
+	if (mb_chan_status_avail(mb_chan))
+		mbox_chan_received_data(mb_chan->chan, mb_chan->rx_msg);
+
+	return IRQ_HANDLED;
+}
+
+static int slimpro_mbox_send_data(struct mbox_chan *chan, void *msg)
+{
+	struct slimpro_mbox_chan *mb_chan =
+				(struct slimpro_mbox_chan *)chan->con_priv;
+
+	mb_chan_send_msg(mb_chan, msg);
+	return 0;
+}
+
+static int slimpro_mbox_startup(struct mbox_chan *chan)
+{
+	struct slimpro_mbox_chan *mb_chan =
+				(struct slimpro_mbox_chan *)chan->con_priv;
+	int rc;
+
+	rc = devm_request_irq(mb_chan->dev, mb_chan->irq, slimpro_mbox_irq, 0,
+			      MBOX_CON_NAME, mb_chan);
+	if (unlikely(rc)) {
+		dev_err(mb_chan->dev, "failed to register mailbox interrupt %d\n",
+			mb_chan->irq);
+		return rc;
+	}
+
+	/* Enable HW interrupt */
+	writel(MBOX_STATUS_ACK_MASK | MBOX_STATUS_AVAIL_MASK,
+	       mb_chan->reg + REG_DB_STAT);
+	mb_chan_enable_int(mb_chan, MBOX_STATUS_ACK_MASK |
+					MBOX_STATUS_AVAIL_MASK);
+	return 0;
+}
+
+static void slimpro_mbox_shutdown(struct mbox_chan *chan)
+{
+	struct slimpro_mbox_chan *mb_chan =
+				(struct slimpro_mbox_chan *)chan->con_priv;
+
+	mb_chan_disable_int(mb_chan, MBOX_STATUS_ACK_MASK |
+				  MBOX_STATUS_AVAIL_MASK);
+	devm_free_irq(mb_chan->dev, mb_chan->irq, mb_chan);
+}
+
+static struct mbox_chan_ops slimpro_mbox_ops = {
+	.send_data = slimpro_mbox_send_data,
+	.startup = slimpro_mbox_startup,
+	.shutdown = slimpro_mbox_shutdown,
+};
+
+static int __init slimpro_mbox_probe(struct platform_device *pdev)
+{
+	struct slimpro_mbox *ctx;
+	struct resource *regs;
+	void __iomem *mb_base;
+	int rc;
+	int i;
+
+	ctx = devm_kzalloc(&pdev->dev, sizeof(struct slimpro_mbox), GFP_KERNEL);
+	if (IS_ERR(ctx))
+		return PTR_ERR(ctx);
+
+	platform_set_drvdata(pdev, ctx);
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mb_base = devm_ioremap(&pdev->dev, regs->start, resource_size(regs));
+	if (IS_ERR(mb_base))
+		return PTR_ERR(mb_base);
+
+	/* Setup mailbox links */
+	for (i = 0; i < MBOX_CNT; i++) {
+		ctx->mc[i].irq = platform_get_irq(pdev, i);
+		if (ctx->mc[i].irq < 0) {
+			dev_err(&pdev->dev, "no IRQ at index %d\n",
+				ctx->mc[i].irq);
+			return -ENODEV;
+		}
+
+		ctx->mc[i].dev = &pdev->dev;
+		ctx->mc[i].reg = mb_base + i * MBOX_REG_SET_OFFSET;
+		ctx->mc[i].id = i;
+		ctx->mc[i].chan = &ctx->chans[i];
+		ctx->chans[i].con_priv = &ctx->mc[i];
+	}
+
+	/* Setup mailbox controller */
+	ctx->mb_ctrl.dev = &pdev->dev;
+	ctx->mb_ctrl.chans = ctx->chans;
+	ctx->mb_ctrl.txdone_irq = true;
+	ctx->mb_ctrl.ops = &slimpro_mbox_ops;
+	ctx->mb_ctrl.num_chans = MBOX_CNT;
+
+	rc = mbox_controller_register(&ctx->mb_ctrl);
+	if (rc) {
+		dev_err(&pdev->dev,
+			"APM X-Gene SLIMpro MailBox register failed:%d\n", rc);
+		return rc;
+	}
+
+	dev_info(&pdev->dev, "APM X-Gene SLIMpro MailBox registered\n");
+	return 0;
+}
+
+static int slimpro_mbox_remove(struct platform_device *pdev)
+{
+	struct slimpro_mbox *smb = platform_get_drvdata(pdev);
+
+	mbox_controller_unregister(&smb->mb_ctrl);
+	return 0;
+}
+
+static const struct of_device_id slimpro_of_match[] = {
+	{.compatible = "apm,xgene-slimpro-mbox" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, slimpro_of_match);
+
+static struct platform_driver slimpro_mbox_driver = {
+	.probe	= slimpro_mbox_probe,
+	.remove = slimpro_mbox_remove,
+	.driver	= {
+		.name = "xgene-slimpro-mbox",
+		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(slimpro_of_match),
+	},
+};
+
+static int __init slimpro_mbox_init(void)
+{
+	return platform_driver_register(&slimpro_mbox_driver);
+}
+
+subsys_initcall(slimpro_mbox_init);
+
+MODULE_DESCRIPTION("APM X-Gene SLIMpro Mailbox Driver");
+MODULE_LICENSE("GPL");