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video: fbdev: vesafb: only support MTRR_TYPE_WRCOMB

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No other video driver uses MTRR types except for MTRR_TYPE_WRCOMB,
the other MTRR types were implemented and supported here but with
no real good reason. The ioremap() APIs are architecture agnostic and
at least on x86 PAT is a new design that extends MTRRs and
can replace it in a much cleaner way, where so long as the
proper ioremap_wc() or variant API is used the right thing will
be done behind the scenes. This is the only driver left using the
other MTRR types -- and since there is no good reason for it now
rip them out.

Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-fbdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
This commit is contained in:
Luis R. Rodriguez 2015-06-04 09:44:46 -07:00 committed by Tomi Valkeinen
parent 99e62ef2ed
commit 87b81762a8
1 changed files with 16 additions and 46 deletions
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62
drivers/video/fbdev/vesafb.c
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@ -404,60 +404,30 @@ static int vesafb_probe(struct platform_device *dev)
* region already (FIXME) */
request_region(0x3c0, 32, "vesafb");
if (mtrr == 3) {
#ifdef CONFIG_MTRR
if (mtrr) {
unsigned int temp_size = size_total;
unsigned int type = 0;
int rc;
switch (mtrr) {
case 1:
type = MTRR_TYPE_UNCACHABLE;
break;
case 2:
type = MTRR_TYPE_WRBACK;
break;
case 3:
type = MTRR_TYPE_WRCOMB;
break;
case 4:
type = MTRR_TYPE_WRTHROUGH;
break;
default:
type = 0;
break;
}
/* Find the largest power-of-two */
temp_size = roundup_pow_of_two(temp_size);
if (type) {
int rc;
/* Find the largest power-of-two */
temp_size = roundup_pow_of_two(temp_size);
/* Try and find a power of two to add */
do {
rc = mtrr_add(vesafb_fix.smem_start, temp_size,
type, 1);
temp_size >>= 1;
} while (temp_size >= PAGE_SIZE && rc == -EINVAL);
}
}
/* Try and find a power of two to add */
do {
rc = mtrr_add(vesafb_fix.smem_start, temp_size,
MTRR_TYPE_WRCOMB, 1);
temp_size >>= 1;
} while (temp_size >= PAGE_SIZE && rc == -EINVAL);
#endif
switch (mtrr) {
case 1: /* uncachable */
info->screen_base = ioremap_nocache(vesafb_fix.smem_start, vesafb_fix.smem_len);
break;
case 2: /* write-back */
info->screen_base = ioremap_cache(vesafb_fix.smem_start, vesafb_fix.smem_len);
break;
case 3: /* write-combining */
info->screen_base = ioremap_wc(vesafb_fix.smem_start, vesafb_fix.smem_len);
break;
case 4: /* write-through */
default:
} else {
#ifdef CONFIG_MTRR
if (mtrr && mtrr != 3)
WARN_ONCE(1, "Only MTRR_TYPE_WRCOMB (3) make sense\n");
#endif
info->screen_base = ioremap(vesafb_fix.smem_start, vesafb_fix.smem_len);
break;
}
if (!info->screen_base) {
printk(KERN_ERR
"vesafb: abort, cannot ioremap video memory 0x%x @ 0x%lx\n",