video: fbdev: vesafb: only support MTRR_TYPE_WRCOMB (87b81762) · Commits · 戴 / test

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>

drivers/video/fbdev/vesafb.c

+16 −46

Original line number	Diff line number	Diff line
		@@ -404,30 +404,9 @@ 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;

		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;
		}

		if (type) {
		int rc;

		/* Find the largest power-of-two */
		@@ -436,28 +415,19 @@ static int vesafb_probe(struct platform_device *dev)
		/* Try and find a power of two to add */
		do {
		rc = mtrr_add(vesafb_fix.smem_start, temp_size,
		type, 1);
		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",

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