Re: [PATCH] ARM: omapfb: Add early framebuffer memory allocator
From: Ivaylo Dimitrov
Date: Sat Feb 13 2016 - 02:26:18 EST
Hi Tomi,
On 11.01.2016 20:34, Tomi Valkeinen wrote:
So, I'm not very enthusiastic about adding this feature as an omapfb
specific boot parameter.
What about something like (not properly formatted, just want your
opinion on the idea):
diff --git a/arch/arm/mach-omap2/fb.c b/arch/arm/mach-omap2/fb.c
index 1f1ecf8..0d109d8 100644
--- a/arch/arm/mach-omap2/fb.c
+++ b/arch/arm/mach-omap2/fb.c
@@ -28,6 +28,7 @@
#include <linux/io.h>
#include <linux/omapfb.h>
#include <linux/dma-mapping.h>
+#include <linux/of_reserved_mem.h>
#include <asm/mach/map.h>
@@ -110,6 +111,49 @@ int __init omap_init_fb(void)
{
return platform_device_register(&omap_fb_device);
}
+
+static int rmem_omapfb_device_init(struct reserved_mem *rmem, struct
device *dev)
+{
+ int dma;
+
+ if (rmem->priv)
+ return 0;
+
+ dma = dma_declare_coherent_memory(&omap_fb_device.dev, rmem->base,
+ rmem->base, rmem->size,
+ DMA_MEMORY_MAP |
+ DMA_MEMORY_EXCLUSIVE);
+
+ if (!(dma & DMA_MEMORY_MAP)) {
+ pr_err("omapfb: dma_declare_coherent_memory failed\n");
+ return -ENOMEM;
+ }
+ else
+ rmem->priv = omap_fb_device.dev.dma_mem;
+
+ return 0;
+}
+
+static void rmem_omapfb_device_release(struct reserved_mem *rmem,
+ struct device *dev)
+{
+ dma_release_declared_memory(&omap_fb_device.dev);
+}
+
+static const struct reserved_mem_ops rmem_omapfb_ops = {
+ .device_init = rmem_omapfb_device_init,
+ .device_release = rmem_omapfb_device_release,
+};
+
+static int __init rmem_omapfb_setup(struct reserved_mem *rmem)
+{
+ rmem->ops = &rmem_omapfb_ops;
+ pr_info("omapfb: reserved %d bytes at %pa\n", rmem->size,
&rmem->base);
+
+ return 0;
+}
+
+RESERVEDMEM_OF_DECLARE(dss, "ti,omapfb-memsize", rmem_omapfb_setup);
#else
int __init omap_init_fb(void) { return 0; }
#endif
diff --git a/arch/arm/mach-omap2/display.c b/arch/arm/mach-omap2/display.c
index 6ab13d1..6f0ba03 100644
--- a/arch/arm/mach-omap2/display.c
+++ b/arch/arm/mach-omap2/display.c
@@ -28,6 +28,7 @@
#include <linux/slab.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
+#include <linux/of_reserved_mem.h>
#include <video/omapdss.h>
#include "omap_hwmod.h"
@@ -640,6 +641,7 @@ int __init omapdss_init_of(void)
omap_display_device.dev.platform_data = &board_data;
r = platform_device_register(&omap_display_device);
+
if (r < 0) {
pr_err("Unable to register omapdss device\n");
return r;
@@ -666,6 +668,9 @@ int __init omapdss_init_of(void)
return r;
}
+ /* Init fb reserved memory, there may be none so ignore the
result */
+ of_reserved_mem_device_init(&pdev->dev);
+
/* create V4L2 display device */
r = omap_init_vout();
if (r < 0) {
Regards,
Ivo