Re: [PATCH 1/2] OMAP: VRFB: convert vrfb to platform device

On Mon, 2012-10-08 at 10:24 -0700, Tony Lindgren wrote:

* Tomi Valkeinen [off-list ref] [121008 05:31]:

quoted

This patch converts vrfb library into a platform device, in an effort to
remove omap dependencies.

The platform device is registered in arch/arm/plat-omap/fb.c and
assigned resources depending on whether running on omap2 or omap3.

The vrfb driver will parse those resources and use them to access vrfb
configuration registers and the vrfb virtual rotation areas.

Signed-off-by: Tomi Valkeinen <redacted>
Cc: Tony Lindgren <tony@atomide.com>
---
 arch/arm/plat-omap/fb.c    |   53 +++++++++++++++++++
 drivers/video/omap2/vrfb.c |  124 +++++++++++++++++++++++++++++++++++++-------
 2 files changed, 157 insertions(+), 20 deletions(-)

diff --git a/arch/arm/plat-omap/fb.c b/arch/arm/plat-omap/fb.c
index dd6f92c..d231912 100644
--- a/arch/arm/plat-omap/fb.c
+++ b/arch/arm/plat-omap/fb.c

@@ -35,6 +35,59 @@
 
 #include <plat/board.h>
 
+#if defined(CONFIG_OMAP2_VRFB)
+static const struct resource omap2_vrfb_resources[] = {
+	DEFINE_RES_MEM(0x68008000u, 0x40),
+	DEFINE_RES_MEM(0x70000000u, 0x4000000),
+	DEFINE_RES_MEM(0x74000000u, 0x4000000),
+	DEFINE_RES_MEM(0x78000000u, 0x4000000),
+	DEFINE_RES_MEM(0x7c000000u, 0x4000000),
+};
+
+static const struct resource omap3_vrfb_resources[] = {
+	DEFINE_RES_MEM(0x6C000180u, 0xc0),
+	DEFINE_RES_MEM(0x70000000u, 0x4000000),
+	DEFINE_RES_MEM(0x74000000u, 0x4000000),
+	DEFINE_RES_MEM(0x78000000u, 0x4000000),
+	DEFINE_RES_MEM(0x7c000000u, 0x4000000),
+	DEFINE_RES_MEM(0xe0000000u, 0x4000000),
+	DEFINE_RES_MEM(0xe4000000u, 0x4000000),
+	DEFINE_RES_MEM(0xe8000000u, 0x4000000),
+	DEFINE_RES_MEM(0xec000000u, 0x4000000),
+	DEFINE_RES_MEM(0xf0000000u, 0x4000000),
+	DEFINE_RES_MEM(0xf4000000u, 0x4000000),
+	DEFINE_RES_MEM(0xf8000000u, 0x4000000),
+	DEFINE_RES_MEM(0xfc000000u, 0x4000000),
+};

Maybe add comments describing what these register are in case
we have a framework handling them at some point later on?

Sure.

quoted

--- a/drivers/video/omap2/vrfb.c
+++ b/drivers/video/omap2/vrfb.c
+#define SMS_ROT_CONTROL(context)	(0x0 + 0x10 * context)
+#define SMS_ROT_SIZE(context)		(0x4 + 0x10 * context)
+#define SMS_ROT_PHYSICAL_BA(context)	(0x8 + 0x10 * context)
+#define SMS_ROT_VIRT_BASE(rot)		(0x1000000 * (rot))

Can you please also remove the old SMS defines and functions
so other code won't start tinkering with them?

Ok.

quoted

+static int __init vrfb_probe(struct platform_device *pdev)
+{
+	struct resource *mem;
+	int i;
+
+	/* first resource is the register res, the rest are vrfb contexts */
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem) {
+		dev_err(&pdev->dev, "can't get vrfb base address\n");
+		return -EINVAL;
+	}

Now that we assume vrfb is the only user of this, so you must do
request_mem_region here as that's the only protection we have.
If that fails here, then we know something is wrong.

Right, I'll add that.

quoted

+	vrfb_base = devm_ioremap(&pdev->dev, mem->start, resource_size(mem));
+	if (!vrfb_base) {
+		dev_err(&pdev->dev, "can't ioremap vrfb memory\n");
+		return -ENOMEM;
+	}
+
+	num_ctxs = pdev->num_resources - 1;
+
+	ctxs = devm_kzalloc(&pdev->dev,
+			sizeof(struct vrfb_ctx) * num_ctxs,
+			GFP_KERNEL);
+
+	if (!ctxs)
+		return -ENOMEM;
+
+	for (i = 0; i < num_ctxs; ++i) {
+		mem = platform_get_resource(pdev, IORESOURCE_MEM, 1 + i);
+		if (!mem) {
+			dev_err(&pdev->dev, "can't get vrfb ctx %d address\n",
+					i);
+			return -EINVAL;
+		}
+
+		ctxs[i].base = mem->start;
+	}

And request_mem_region must also be done for these registers to make
sure no other code is using them. Again, if it fails, something is
wrong.

There's already request_mem_region for the VRFB virtual areas, which is
done later when omapfb or somebody else requests a vrfb context with
omap_vrfb_request_ctx(). The memory areas (they are rotated
framebuffers, not registers as such) are not used until then.

 Tomi