omap3-iommu: reorganize

Commit Message

Felipe Contreras May 18, 2009, 4:43 p.m. UTC

No functional changes.

Signed-off-by: Felipe Contreras <[e-mail]>
---

How about this?

 arch/arm/mach-omap2/omap3-iommu.c |   53 ++++++++++++++++++-------------------
 1 files changed, 26 insertions(+), 27 deletions(-)

Comments

Felipe Contreras May 19, 2009, 9:43 a.m. UTC | #1

On Tue, May 19, 2009 at 9:03 AM, Hiroshi DOYU <[e-mail]> wrote:
> From: ext Felipe Contreras <[e-mail]>
> Subject: [PATCH] omap3-iommu: reorganize
> Date: Mon, 18 May 2009 18:43:00 +0200
>
>> No functional changes.
>>
>> Signed-off-by: Felipe Contreras <[e-mail]>
>> ---
>>
>> How about this?
>
> What's the advantage of introducing a new structure here?

That instead of having 3 arrays with potentially different sizes:

iommu_base
iommu_irq
omap3_iommu_pdata

You have one:

devices

Also, think about the hypothetical situation where you need 2 more
iommu devices (maybe OMAP4?). What would you need to do? You'll need
to add OMAP3_MMU3_BASE and OMAP3_MMU4_BASE add them to iommu_base,
then add OMAP3_MMU3_IRQ and OMAP3_MMU4_IRQ and put them to iommu_irq,
finally add the device data to omap3_iommu_pdata.

In the process a simple mistake would be easy to overlook:

static unsigned long iommu_base[] __initdata = {
       OMAP3_MMU1_BASE,
       OMAP3_MMU2_BASE,
+       OMAP3_MMU3_BASE,
+       OMAP3_MMU2_BASE,
};

With the 'devices' array you just need to add two more elements and
that's it. It leaves less room for mistakes.

However 'struct iommu_device' is a local structure, it could very well
be called __foobar__, nobody outside omap3-iommu.c will see it anyway.

Patch

diff --git a/arch/arm/mach-omap2/omap3-iommu.c b/arch/arm/mach-omap2/omap3-iommu.c
index 91ee38a..50bd445 100644
--- a/arch/arm/mach-omap2/omap3-iommu.c
+++ b/arch/arm/mach-omap2/omap3-iommu.c
@@ -14,32 +14,30 @@ 
 
 #include <mach/iommu.h>
 
-#define OMAP3_MMU1_BASE	0x480bd400
-#define OMAP3_MMU2_BASE	0x5d000000
-#define OMAP3_MMU1_IRQ	24
-#define OMAP3_MMU2_IRQ	28
-
-
-static unsigned long iommu_base[] __initdata = {
-	OMAP3_MMU1_BASE,
-	OMAP3_MMU2_BASE,
-};
-
-static int iommu_irq[] __initdata = {
-	OMAP3_MMU1_IRQ,
-	OMAP3_MMU2_IRQ,
+struct iommu_device {
+	resource_size_t base;
+	int irq;
+	struct iommu_platform_data pdata;
 };
 
-static const struct iommu_platform_data omap3_iommu_pdata[] __initconst = {
+static struct iommu_device devices[] __initdata = {
 	{
-		.name = "isp",
-		.nr_tlb_entries = 8,
-		.clk_name = "cam_ick",
+		.base = 0x480bd400,
+		.irq = 24,
+		.pdata = {
+			.name = "isp",
+			.nr_tlb_entries = 8,
+			.clk_name = "cam_ick",
+		},
 	},
 	{
-		.name = "iva2",
-		.nr_tlb_entries = 32,
-		.clk_name = "iva2_ck",
+		.base = 0x5d000000,
+		.irq = 28,
+		.pdata = {
+			.name = "iva2",
+			.nr_tlb_entries = 32,
+			.clk_name = "iva2_ck",
+		},
 	},
 };
 #define NR_IOMMU_DEVICES ARRAY_SIZE(omap3_iommu_pdata)
@@ -52,6 +50,7 @@  static int __init omap3_iommu_init(void)
 
 	for (i = 0; i < NR_IOMMU_DEVICES; i++) {
 		struct platform_device *pdev;
+		const struct iommu_device *d = &devices[i];
 		struct resource res[2];
 
 		pdev = platform_device_alloc("omap-iommu", i);
@@ -60,19 +59,19 @@  static int __init omap3_iommu_init(void)
 			goto err_out;
 		}
 
-		memset(res, 0,  sizeof(res));
-		res[0].start = iommu_base[i];
-		res[0].end = iommu_base[i] + MMU_REG_SIZE - 1;
+		memset(res, 0, sizeof(res));
+		res[0].start = d->base;
+		res[0].end = d->base + MMU_REG_SIZE - 1;
 		res[0].flags = IORESOURCE_MEM;
-		res[1].start = res[1].end = iommu_irq[i];
+		res[1].start = res[1].end = d->irq;
 		res[1].flags = IORESOURCE_IRQ;
 
 		err = platform_device_add_resources(pdev, res,
 						    ARRAY_SIZE(res));
 		if (err)
 			goto err_out;
-		err = platform_device_add_data(pdev, &omap3_iommu_pdata[i],
-					       sizeof(omap3_iommu_pdata[0]));
+		err = platform_device_add_data(pdev, &d->pdata,
+					       sizeof(d->pdata));
 		if (err)
 			goto err_out;
 		err = platform_device_add(pdev);