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[8/10] omap mailbox: OMAP4-Mailbox - Adds code changes to support OMAP4 mailbox.

Message ID B85A65D85D7EB246BE421B3FB0FBB59301DD6108F2@dbde02.ent.ti.com (mailing list archive)
State Superseded, archived
Headers show

Commit Message

C.A, Subramaniam Sept. 4, 2009, 11:48 a.m. UTC 
From eeaa22aff9df8027f91884ee78328028bd5a6782 Mon Sep 17 00:00:00 2001
From: C A Subramaniam <subramaniam.ca@ti.com>
Date: Thu, 3 Sep 2009 17:53:27 +0530
Subject: [PATCH 8/10] omap mailbox: OMAP4-Mailbox - Adds code changes to support OMAP4 mailbox.

This patch adds code changes in the mailbox driver module to
add support for OMAP4 mailbox.

Signed-off-by: Hari Kanigeri <h-kanigeri2@ti.com>
Signed-off-by: C A Subramaniam <subramaniam.ca@ti.com>
Signed-off-by: Ramesh Gupta G <grgupta@ti.com>
---
 arch/arm/mach-omap2/mailbox.c |  156 +++++++++++++++++++++++++++++++++--------
 1 files changed, 125 insertions(+), 31 deletions(-)

Comments

Russell King Sept. 7, 2009, 3:05 p.m. UTC | #1 
On Fri, Sep 04, 2009 at 05:18:11PM +0530, C.A, Subramaniam wrote:
> @@ -70,31 +89,37 @@ static inline void mbox_write_reg(u32 val, size_t ofs)
>  static int omap2_mbox_startup(struct omap_mbox *mbox)
>  {
>  	unsigned int l;
> +	if (!mbox_configured) {
> +		mbox_ick_handle = clk_get(NULL, "mailboxes_ick");
> +		if (IS_ERR(mbox_ick_handle)) {
> +			printk(KERN_ERR "Could not get mailboxes_ick\n");
> +			return -ENODEV;
> +		}
> +		clk_enable(mbox_ick_handle);
>  
> -	mbox_ick_handle = clk_get(NULL, "mailboxes_ick");
> -	if (IS_ERR(mbox_ick_handle)) {
> -		printk("Could not get mailboxes_ick\n");
> -		return -ENODEV;
> -	}
> -	clk_enable(mbox_ick_handle);
> -
> -	l = mbox_read_reg(MAILBOX_REVISION);
> -	pr_info("omap mailbox rev %d.%d\n", (l & 0xf0) >> 4, (l & 0x0f));
> -
> -	/* set smart-idle & autoidle */
> -	l = mbox_read_reg(MAILBOX_SYSCONFIG);
> -	l |= 0x00000011;
> -	mbox_write_reg(l, MAILBOX_SYSCONFIG);
> +		l = mbox_read_reg(MAILBOX_REVISION);
> +		pr_info("omap mailbox rev %d.%d\n", (l & 0xf0) >> 4,
> +							(l & 0x0f));
>  
> +		/* set smart-idle & autoidle */
> +		l = mbox_read_reg(MAILBOX_SYSCONFIG);
> +		l |= 0x00000011;
> +		mbox_write_reg(l, MAILBOX_SYSCONFIG);
> +	}
> +	mbox_configured++;

I assume you're doing this because this function can be called multiple
times.  What protects this against races?

>  	omap2_mbox_enable_irq(mbox, IRQ_RX);
>  
>  	return 0;
>  }
>  
>  static void omap2_mbox_shutdown(struct omap_mbox *mbox)
> -{
> -	clk_disable(mbox_ick_handle);
> -	clk_put(mbox_ick_handle);
> +{	if (mbox_configured > 0)
> +		mbox_configured--;
> +		if (!mbox_configured) {
> +			clk_disable(mbox_ick_handle);
> +			clk_put(mbox_ick_handle);
> +			mbox_ick_handle = NULL;
> +		}

Same concern - what protects mbox_configured and the associated code against
races?
C.A, Subramaniam Sept. 7, 2009, 3:12 p.m. UTC | #2 
Hi Russell,
Yes, that needs to be taken care of. Hiroshi has suggested that we move this logic into the omap_mbox_get() function.
Will add code to protect from races conditions while making the change.

Thank you and Regards
Subbu


> -----Original Message-----
> From: Russell King [mailto:rmk@arm.linux.org.uk] 
> Sent: Monday, September 07, 2009 8:35 PM
> To: C.A, Subramaniam
> Cc: linux-omap@vger.kernel.org; tony@atomide.com; 
> Hiroshi.DOYU@nokia.com; Kanigeri, Hari; Gupta, Ramesh
> Subject: Re: [PATCH 8/10] omap mailbox: OMAP4-Mailbox - Adds 
> code changes to support OMAP4 mailbox.
> 
> On Fri, Sep 04, 2009 at 05:18:11PM +0530, C.A, Subramaniam wrote:
> > @@ -70,31 +89,37 @@ static inline void mbox_write_reg(u32 
> val, size_t 
> > ofs)  static int omap2_mbox_startup(struct omap_mbox *mbox)  {
> >  	unsigned int l;
> > +	if (!mbox_configured) {
> > +		mbox_ick_handle = clk_get(NULL, "mailboxes_ick");
> > +		if (IS_ERR(mbox_ick_handle)) {
> > +			printk(KERN_ERR "Could not get 
> mailboxes_ick\n");
> > +			return -ENODEV;
> > +		}
> > +		clk_enable(mbox_ick_handle);
> >  
> > -	mbox_ick_handle = clk_get(NULL, "mailboxes_ick");
> > -	if (IS_ERR(mbox_ick_handle)) {
> > -		printk("Could not get mailboxes_ick\n");
> > -		return -ENODEV;
> > -	}
> > -	clk_enable(mbox_ick_handle);
> > -
> > -	l = mbox_read_reg(MAILBOX_REVISION);
> > -	pr_info("omap mailbox rev %d.%d\n", (l & 0xf0) >> 4, (l 
> & 0x0f));
> > -
> > -	/* set smart-idle & autoidle */
> > -	l = mbox_read_reg(MAILBOX_SYSCONFIG);
> > -	l |= 0x00000011;
> > -	mbox_write_reg(l, MAILBOX_SYSCONFIG);
> > +		l = mbox_read_reg(MAILBOX_REVISION);
> > +		pr_info("omap mailbox rev %d.%d\n", (l & 0xf0) >> 4,
> > +							(l & 0x0f));
> >  
> > +		/* set smart-idle & autoidle */
> > +		l = mbox_read_reg(MAILBOX_SYSCONFIG);
> > +		l |= 0x00000011;
> > +		mbox_write_reg(l, MAILBOX_SYSCONFIG);
> > +	}
> > +	mbox_configured++;
> 
> I assume you're doing this because this function can be 
> called multiple times.  What protects this against races?
> 
> >  	omap2_mbox_enable_irq(mbox, IRQ_RX);
> >  
> >  	return 0;
> >  }
> >  
> >  static void omap2_mbox_shutdown(struct omap_mbox *mbox) -{
> > -	clk_disable(mbox_ick_handle);
> > -	clk_put(mbox_ick_handle);
> > +{	if (mbox_configured > 0)
> > +		mbox_configured--;
> > +		if (!mbox_configured) {
> > +			clk_disable(mbox_ick_handle);
> > +			clk_put(mbox_ick_handle);
> > +			mbox_ick_handle = NULL;
> > +		}
> 
> Same concern - what protects mbox_configured and the 
> associated code against races?
> 
> --
> Russell King
>  Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
>  maintainer of:
> 
> --
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diff mbox

Patch

diff --git a/arch/arm/mach-omap2/mailbox.c b/arch/arm/mach-omap2/mailbox.c
index 6f71f37..4ab3e1d 100644
--- a/arch/arm/mach-omap2/mailbox.c
+++ b/arch/arm/mach-omap2/mailbox.c
@@ -18,21 +18,36 @@ 
 #include <mach/mailbox.h>
 #include <mach/irqs.h>
 
+#define DRV_NAME "omap2-mailbox"
+
 #define MAILBOX_REVISION		0x000
 #define MAILBOX_SYSCONFIG		0x010
 #define MAILBOX_SYSSTATUS		0x014
 #define MAILBOX_MESSAGE(m)		(0x040 + 4 * (m))
 #define MAILBOX_FIFOSTATUS(m)		(0x080 + 4 * (m))
 #define MAILBOX_MSGSTATUS(m)		(0x0c0 + 4 * (m))
+
+#ifdef CONFIG_ARCH_OMAP4
+#define MAILBOX_IRQSTATUS(u)		(0x104 + 10 * (u))
+#define MAILBOX_IRQENABLE(u)		(0x108 + 10 * (u))
+#define MAILBOX_IRQENABLE_CLR(u)	(0x10c + 10 * (u))
+#else
 #define MAILBOX_IRQSTATUS(u)		(0x100 + 8 * (u))
 #define MAILBOX_IRQENABLE(u)		(0x104 + 8 * (u))
+#endif
 
-#define MAILBOX_IRQ_NEWMSG(u)		(1 << (2 * (u)))
-#define MAILBOX_IRQ_NOTFULL(u)		(1 << (2 * (u) + 1))
+#define MAILBOX_IRQ_NEWMSG(m)		(1 << (2 * (m)))
+#define MAILBOX_IRQ_NOTFULL(m)		(1 << (2 * (m) + 1))
 
+#ifdef CONFIG_ARCH_OMAP4
+#define MBOX_REG_SIZE			0x130
+#else
 #define MBOX_REG_SIZE			0x120
+#endif
+
 #define MBOX_NR_REGS			(MBOX_REG_SIZE / sizeof(u32))
 
+
 static void __iomem *mbox_base;
 
 struct omap_mbox2_fifo {
@@ -49,9 +64,13 @@  struct omap_mbox2_priv {
 	u32 newmsg_bit;
 	u32 notfull_bit;
 	u32 ctx[MBOX_NR_REGS];
+#ifdef CONFIG_ARCH_OMAP4
+	unsigned long irqdisable;
+#endif
 };
 
 static struct clk *mbox_ick_handle;
+static int mbox_configured;
 
 static void omap2_mbox_enable_irq(struct omap_mbox *mbox,
 				  omap_mbox_type_t irq);
@@ -70,31 +89,37 @@  static inline void mbox_write_reg(u32 val, size_t ofs)
 static int omap2_mbox_startup(struct omap_mbox *mbox)
 {
 	unsigned int l;
+	if (!mbox_configured) {
+		mbox_ick_handle = clk_get(NULL, "mailboxes_ick");
+		if (IS_ERR(mbox_ick_handle)) {
+			printk(KERN_ERR "Could not get mailboxes_ick\n");
+			return -ENODEV;
+		}
+		clk_enable(mbox_ick_handle);
 
-	mbox_ick_handle = clk_get(NULL, "mailboxes_ick");
-	if (IS_ERR(mbox_ick_handle)) {
-		printk("Could not get mailboxes_ick\n");
-		return -ENODEV;
-	}
-	clk_enable(mbox_ick_handle);
-
-	l = mbox_read_reg(MAILBOX_REVISION);
-	pr_info("omap mailbox rev %d.%d\n", (l & 0xf0) >> 4, (l & 0x0f));
-
-	/* set smart-idle & autoidle */
-	l = mbox_read_reg(MAILBOX_SYSCONFIG);
-	l |= 0x00000011;
-	mbox_write_reg(l, MAILBOX_SYSCONFIG);
+		l = mbox_read_reg(MAILBOX_REVISION);
+		pr_info("omap mailbox rev %d.%d\n", (l & 0xf0) >> 4,
+							(l & 0x0f));
 
+		/* set smart-idle & autoidle */
+		l = mbox_read_reg(MAILBOX_SYSCONFIG);
+		l |= 0x00000011;
+		mbox_write_reg(l, MAILBOX_SYSCONFIG);
+	}
+	mbox_configured++;
 	omap2_mbox_enable_irq(mbox, IRQ_RX);
 
 	return 0;
 }
 
 static void omap2_mbox_shutdown(struct omap_mbox *mbox)
-{
-	clk_disable(mbox_ick_handle);
-	clk_put(mbox_ick_handle);
+{	if (mbox_configured > 0)
+		mbox_configured--;
+		if (!mbox_configured) {
+			clk_disable(mbox_ick_handle);
+			clk_put(mbox_ick_handle);
+			mbox_ick_handle = NULL;
+		}
 }
 
 /* Mailbox FIFO handle functions */
@@ -123,7 +148,7 @@  static int omap2_mbox_fifo_full(struct omap_mbox *mbox)
 {
 	struct omap_mbox2_fifo *fifo =
 		&((struct omap_mbox2_priv *)mbox->priv)->tx_fifo;
-	return (mbox_read_reg(fifo->fifo_stat));
+	return mbox_read_reg(fifo->fifo_stat);
 }
 
 /* Mailbox IRQ handle functions */
@@ -143,10 +168,9 @@  static void omap2_mbox_disable_irq(struct omap_mbox *mbox,
 {
 	struct omap_mbox2_priv *p = (struct omap_mbox2_priv *)mbox->priv;
 	u32 l, bit = (irq == IRQ_TX) ? p->notfull_bit : p->newmsg_bit;
-
-	l = mbox_read_reg(p->irqenable);
+	l = mbox_read_reg(p->irqdisable);
 	l &= ~bit;
-	mbox_write_reg(l, p->irqenable);
+	mbox_write_reg(l, p->irqdisable);
 }
 
 static void omap2_mbox_ack_irq(struct omap_mbox *mbox,
@@ -156,6 +180,8 @@  static void omap2_mbox_ack_irq(struct omap_mbox *mbox,
 	u32 bit = (irq == IRQ_TX) ? p->notfull_bit : p->newmsg_bit;
 
 	mbox_write_reg(bit, p->irqstatus);
+	/* Flush post writing */
+	 mbox_read_reg(p->irqstatus);
 }
 
 static int omap2_mbox_is_irq(struct omap_mbox *mbox,
@@ -166,7 +192,7 @@  static int omap2_mbox_is_irq(struct omap_mbox *mbox,
 	u32 enable = mbox_read_reg(p->irqenable);
 	u32 status = mbox_read_reg(p->irqstatus);
 
-	return (enable & status & bit);
+	return (int)(enable & status & bit);
 }
 
 static void omap2_mbox_save_ctx(struct omap_mbox *mbox)
@@ -219,9 +245,12 @@  static struct omap_mbox_ops omap2_mbox_ops = {
  */
 
 /* FIXME: the following structs should be filled automatically by the user id */
-
+#ifdef CONFIG_ARCH_OMAP4
+static struct omap_mbox2_priv omap2_mbox_1_priv = {
+#else
 /* DSP */
 static struct omap_mbox2_priv omap2_mbox_dsp_priv = {
+#endif
 	.tx_fifo = {
 		.msg		= MAILBOX_MESSAGE(0),
 		.fifo_stat	= MAILBOX_FIFOSTATUS(0),
@@ -234,7 +263,19 @@  static struct omap_mbox2_priv omap2_mbox_dsp_priv = {
 	.irqstatus	= MAILBOX_IRQSTATUS(0),
 	.notfull_bit	= MAILBOX_IRQ_NOTFULL(0),
 	.newmsg_bit	= MAILBOX_IRQ_NEWMSG(1),
+#ifdef CONFIG_ARCH_OMAP4
+	.irqdisable	= MAILBOX_IRQENABLE_CLR(0),
+#endif
+};
+
+#ifdef CONFIG_ARCH_OMAP4
+struct omap_mbox mbox_1_info = {
+	.name	= "mailbox-1",
+	.ops	= &omap2_mbox_ops,
+	.priv	= &omap2_mbox_1_priv,
 };
+EXPORT_SYMBOL(mbox_1_info);
+#else
 
 struct omap_mbox mbox_dsp_info = {
 	.name	= "dsp",
@@ -242,6 +283,33 @@  struct omap_mbox mbox_dsp_info = {
 	.priv	= &omap2_mbox_dsp_priv,
 };
 EXPORT_SYMBOL(mbox_dsp_info);
+#endif
+
+#ifdef CONFIG_ARCH_OMAP4
+static struct omap_mbox2_priv omap2_mbox_2_priv = {
+	.tx_fifo = {
+		.msg		= MAILBOX_MESSAGE(3),
+		.fifo_stat	= MAILBOX_FIFOSTATUS(3),
+	},
+	.rx_fifo = {
+		.msg		= MAILBOX_MESSAGE(2),
+		.msg_stat	= MAILBOX_MSGSTATUS(2),
+	},
+	.irqenable	= MAILBOX_IRQENABLE(0),
+	.irqstatus	= MAILBOX_IRQSTATUS(0),
+	.notfull_bit	= MAILBOX_IRQ_NOTFULL(3),
+	.newmsg_bit	= MAILBOX_IRQ_NEWMSG(2),
+	.irqdisable     = MAILBOX_IRQENABLE_CLR(0),
+};
+
+struct omap_mbox mbox_2_info = {
+	.name	= "mailbox-2",
+	.ops	= &omap2_mbox_ops,
+	.priv	= &omap2_mbox_2_priv,
+};
+EXPORT_SYMBOL(mbox_2_info);
+#endif
+
 
 #if defined(CONFIG_ARCH_OMAP2420) /* IVA */
 static struct omap_mbox2_priv omap2_mbox_iva_priv = {
@@ -282,17 +350,31 @@  static int __devinit omap2_mbox_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	/* DSP or IVA2 IRQ */
-	ret = platform_get_irq(pdev, 0);
-	if (ret < 0) {
+	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+
+	if (unlikely(!res)) {
 		dev_err(&pdev->dev, "invalid irq resource\n");
+		ret = -ENODEV;
 		goto err_dsp;
 	}
-	mbox_dsp_info.irq = ret;
-
+#ifdef CONFIG_ARCH_OMAP4
+	mbox_1_info.irq = res->start;
+	ret = omap_mbox_register(&pdev->dev, &mbox_1_info);
+#else
+	mbox_dsp_info.irq = res->start;
 	ret = omap_mbox_register(&pdev->dev, &mbox_dsp_info);
+#endif
 	if (ret)
 		goto err_dsp;
 
+#ifdef CONFIG_ARCH_OMAP4
+
+	mbox_2_info.irq = res->start;
+	ret = omap_mbox_register(&pdev->dev, &mbox_2_info);
+	if (ret)
+		goto err_mbox_2;
+#endif
+
 #if defined(CONFIG_ARCH_OMAP2420) /* IVA */
 	if (cpu_is_omap2420()) {
 		/* IVA IRQ */
@@ -310,8 +392,14 @@  static int __devinit omap2_mbox_probe(struct platform_device *pdev)
 #endif
 	return 0;
 
+#ifdef CONFIG_ARCH_OMAP4
+err_mbox_2:
+	omap_mbox_unregister(&mbox_1_info);
+#else
 err_iva1:
 	omap_mbox_unregister(&mbox_dsp_info);
+#endif
+
 err_dsp:
 	iounmap(mbox_base);
 	return ret;
@@ -322,7 +410,13 @@  static int __devexit omap2_mbox_remove(struct platform_device *pdev)
 #if defined(CONFIG_ARCH_OMAP2420)
 	omap_mbox_unregister(&mbox_iva_info);
 #endif
+
+#ifdef CONFIG_ARCH_OMAP4
+	omap_mbox_unregister(&mbox_2_info);
+	omap_mbox_unregister(&mbox_1_info);
+#else
 	omap_mbox_unregister(&mbox_dsp_info);
+#endif
 	iounmap(mbox_base);
 	return 0;
 }
@@ -331,7 +425,7 @@  static struct platform_driver omap2_mbox_driver = {
 	.probe = omap2_mbox_probe,
 	.remove = __devexit_p(omap2_mbox_remove),
 	.driver = {
-		.name = "omap2-mailbox",
+		.name = DRV_NAME,
 	},
 };
 
@@ -351,4 +445,4 @@  module_exit(omap2_mbox_exit);
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("omap mailbox: omap2/3 architecture specific functions");
 MODULE_AUTHOR("Hiroshi DOYU <Hiroshi.DOYU@nokia.com>, Paul Mundt");
-MODULE_ALIAS("platform:omap2-mailbox");
+MODULE_ALIAS("platform:"DRV_NAME);