video: fbdev: controlfb: add COMPILE_TEST support

Add COMPILE_TEST support to controlfb driver for better compile
testing coverage.

While at it:
- convert driver to use eieio() and dcbf() helpers instead of
  open-coding them
- add invalid_vram_cache() helper to avoid code duplication

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324134508.25120-3-b.zolnierkie@samsung.com

diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
index 91b0a71..fa88e8b 100644 (file)
--- a/drivers/video/fbdev/Kconfig
+++ b/drivers/video/fbdev/Kconfig
@@ -472,7 +472,7 @@ config FB_OF
 
 config FB_CONTROL
        bool "Apple \"control\" display support"
-       depends on (FB = y) && PPC_PMAC && PPC32
+       depends on (FB = y) && ((PPC_PMAC && PPC32) || COMPILE_TEST)
        select FB_CFB_FILLRECT
        select FB_CFB_COPYAREA
        select FB_CFB_IMAGEBLIT

diff --git a/drivers/video/fbdev/controlfb.c b/drivers/video/fbdev/controlfb.c
index 50fc52f..5442318 100644 (file)
--- a/drivers/video/fbdev/controlfb.c
+++ b/drivers/video/fbdev/controlfb.c
@@ -48,12 +48,37 @@
 #include <linux/nvram.h>
 #include <linux/adb.h>
 #include <linux/cuda.h>
+#ifdef CONFIG_PPC_PMAC
 #include <asm/prom.h>
 #include <asm/btext.h>
+#endif
 
 #include "macmodes.h"
 #include "controlfb.h"
 
+#ifndef CONFIG_PPC_PMAC
+#define invalid_vram_cache(addr)
+#undef in_8
+#undef out_8
+#undef in_le32
+#undef out_le32
+#define in_8(addr)             0
+#define out_8(addr, val)
+#define in_le32(addr)          0
+#define out_le32(addr, val)
+#define pgprot_cached_wthru(prot) (prot)
+#else
+static void invalid_vram_cache(void __force *addr)
+{
+       eieio();
+       dcbf(addr);
+       mb();
+       eieio();
+       dcbf(addr);
+       mb();
+}
+#endif
+
 struct fb_par_control {
        int     vmode, cmode;
        int     xres, yres;
@@ -309,7 +334,7 @@ static int controlfb_mmap(struct fb_info *info,
 
 static int controlfb_blank(int blank_mode, struct fb_info *info)
 {
-       struct fb_info_control *p =
+       struct fb_info_control __maybe_unused *p =
                container_of(info, struct fb_info_control, info);
        unsigned ctrl;
 
@@ -605,12 +630,7 @@ static void __init find_vram_size(struct fb_info_control *p)
 
        out_8(&p->frame_buffer[0x600000], 0xb3);
        out_8(&p->frame_buffer[0x600001], 0x71);
-       asm volatile("eieio; dcbf 0,%0" : : "r" (&p->frame_buffer[0x600000])
-                                       : "memory" );
-       mb();
-       asm volatile("eieio; dcbi 0,%0" : : "r" (&p->frame_buffer[0x600000])
-                                       : "memory" );
-       mb();
+       invalid_vram_cache(&p->frame_buffer[0x600000]);
 
        bank2 = (in_8(&p->frame_buffer[0x600000]) == 0xb3)
                && (in_8(&p->frame_buffer[0x600001]) == 0x71);
@@ -624,12 +644,7 @@ static void __init find_vram_size(struct fb_info_control *p)
 
        out_8(&p->frame_buffer[0], 0x5a);
        out_8(&p->frame_buffer[1], 0xc7);
-       asm volatile("eieio; dcbf 0,%0" : : "r" (&p->frame_buffer[0])
-                                       : "memory" );
-       mb();
-       asm volatile("eieio; dcbi 0,%0" : : "r" (&p->frame_buffer[0])
-                                       : "memory" );
-       mb();
+       invalid_vram_cache(&p->frame_buffer[0]);
 
        bank1 = (in_8(&p->frame_buffer[0]) == 0x5a)
                && (in_8(&p->frame_buffer[1]) == 0xc7);