Re: [RFC PATCH] fbdev: maxinefb: fix build issues
From: Philippe Mathieu-Daudé
Date: Sun Aug 09 2026 - 23:25:04 EST
Hi Randy,
On 10/8/26 01:48, Randy Dunlap wrote:
This is all ancient source code from the beginning of git time.
Now builds cleanly on 32-bit and 64-bit MACH_DECSTATION.
Fixes these build errors/warnings:
../drivers/video/fbdev/maxinefb.c:64:6: warning: no previous prototype for 'maxinefb_ims332_write_register' [-Wmissing-prototypes]
64 | void maxinefb_ims332_write_register(int regno, register unsigned int val)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ../drivers/video/fbdev/maxinefb.c:34:
../drivers/video/fbdev/maxinefb.c: In function 'maxinefb_ims332_write_register':
../include/video/maxinefb.h:16:41: error: implicit declaration of function 'KSEG1ADDR'; did you mean 'CKSEG1ADDR'? [-Wimplicit-function-declaration]
16 | #define MAXINEFB_IMS332_ADDRESS KSEG1ADDR(0x1c140000)
| ^~~~~~~~~
../drivers/video/fbdev/maxinefb.c:66:49: note: in expansion of macro 'MAXINEFB_IMS332_ADDRESS'
66 | register unsigned char *regs = (char *) MAXINEFB_IMS332_ADDRESS;
| ^~~~~~~~~~~~~~~~~~~~~~~
../drivers/video/fbdev/maxinefb.c:66:40: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
66 | register unsigned char *regs = (char *) MAXINEFB_IMS332_ADDRESS;
| ^
../drivers/video/fbdev/maxinefb.c: At top level:
../drivers/video/fbdev/maxinefb.c:74:14: warning: no previous prototype for 'maxinefb_ims332_read_register' [-Wmissing-prototypes]
74 | unsigned int maxinefb_ims332_read_register(int regno)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../drivers/video/fbdev/maxinefb.c: At top level:
../drivers/video/fbdev/maxinefb.c:74:21: warning: 'maxinefb_ims332_read_register' defined but not used [-Wunused-function]
74 | static unsigned int maxinefb_ims332_read_register(int regno)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../drivers/video/fbdev/maxinefb.c: In function 'maxinefb_ims332_read_register':
../drivers/video/fbdev/maxinefb.c:76:40: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
76 | register unsigned char *regs = (char *) MAXINEFB_IMS332_ADDRESS;
| ^
../drivers/video/fbdev/maxinefb.c: At top level:
../drivers/video/fbdev/maxinefb.c:114:12: warning: no previous prototype for 'maxinefb_init' [-Wmissing-prototypes]
114 | int __init maxinefb_init(void)
| ^~~~~~~~~~~~~
In file included from ../drivers/video/fbdev/maxinefb.c:34:
../drivers/video/fbdev/maxinefb.c: In function 'maxinefb_init':
../include/video/maxinefb.h:22:41: error: implicit declaration of function 'KSEG1ADDR'; did you mean 'CKSEG1ADDR'? [-Wimplicit-function-declaration]
22 | #define DS5000_xx_ONBOARD_FBMEM_START KSEG1ADDR(0x0a000000)
| ^~~~~~~~~
../drivers/video/fbdev/maxinefb.c:119:20: note: in expansion of macro 'DS5000_xx_ONBOARD_FBMEM_START'
119 | fb_start = DS5000_xx_ONBOARD_FBMEM_START;
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Suggested-by: "Maciej W. Rozycki" <macro@xxxxxxxxxxx> # for s/KSEG1ADDR/CKSEG1ADDR/
Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
---
Cc: "Maciej W. Rozycki" <macro@xxxxxxxxxxx>
Cc: Helge Deller <deller@xxxxxx>
Cc: linux-fbdev@xxxxxxxxxxxxxxx
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxxx
drivers/video/fbdev/maxinefb.c | 17 ++---------------
include/video/maxinefb.h | 4 ++--
2 files changed, 4 insertions(+), 17 deletions(-)
--- linux-next-20260807.orig/drivers/video/fbdev/maxinefb.c
+++ linux-next-20260807/drivers/video/fbdev/maxinefb.c
@@ -61,7 +61,7 @@ static struct fb_fix_screeninfo maxinefb
/* Handle the funny Inmos RamDAC/video controller ... */
-void maxinefb_ims332_write_register(int regno, register unsigned int val)
+static void maxinefb_ims332_write_register(int regno, register unsigned int val)
{
register unsigned char *regs = (char *) MAXINEFB_IMS332_ADDRESS;
unsigned char *wptr;
@@ -71,19 +71,6 @@ void maxinefb_ims332_write_register(int
*((volatile unsigned short *) (wptr)) = val;
}
-unsigned int maxinefb_ims332_read_register(int regno)
-{
- register unsigned char *regs = (char *) MAXINEFB_IMS332_ADDRESS;
- unsigned char *rptr;
- register unsigned int j, k;
-
- rptr = regs + 0x80000 + (regno << 4);
- j = *((volatile unsigned short *) rptr);
- k = *((volatile unsigned short *) regs);
-
- return (j & 0xffff) | ((k & 0xff00) << 8);
-}
-
/* Set the palette */
static int maxinefb_setcolreg(unsigned regno, unsigned red, unsigned green,
unsigned blue, unsigned transp, struct fb_info *info)
@@ -111,7 +98,7 @@ static const struct fb_ops maxinefb_ops
.fb_setcolreg = maxinefb_setcolreg,
};
-int __init maxinefb_init(void)
+static int __init maxinefb_init(void)
{
unsigned long fboff;
unsigned long fb_start;
--- linux-next-20260807.orig/include/video/maxinefb.h
+++ linux-next-20260807/include/video/maxinefb.h
@@ -13,13 +13,13 @@
/*
* IMS332 video controller register base address
*/
-#define MAXINEFB_IMS332_ADDRESS KSEG1ADDR(0x1c140000)
+#define MAXINEFB_IMS332_ADDRESS CKSEG1ADDR(0x1c140000)
/*
* Begin of DECstation 5000/xx onboard framebuffer memory, default resolution
* is 1024x768x8
*/
-#define DS5000_xx_ONBOARD_FBMEM_START KSEG1ADDR(0x0a000000)
+#define DS5000_xx_ONBOARD_FBMEM_START CKSEG1ADDR(0x0a000000)
The change looks correct, but clearly this has never been tested
on a 64-bit DECstation, so I'm not sure having this code being
now built is an improvement.
What about:
-- >8 --
diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
index ac9ac4287c6a..ff17afe6b8b3 100644
--- a/drivers/video/fbdev/Kconfig
+++ b/drivers/video/fbdev/Kconfig
@@ -1436,7 +1436,7 @@ config FB_PMAGB_B
config FB_MAXINE
bool "Maxine (Personal DECstation) onboard framebuffer support"
- depends on (FB = y) && MACH_DECSTATION
+ depends on (FB = y) && MACH_DECSTATION && 32BIT
select FB_IOMEM_HELPERS
help
Support for the onboard framebuffer (1024x768x8) in the Personal
---
?
Regards,
Phil.