[PATCH] video: fbdev: atyfb: only use ioremap_uc() on i386 and ia64

From: Arnd Bergmann <arnd@arndb.de>
To: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Christoph Hellwig <hch@lst.de>,
	x86@kernel.org, Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	linux-ia64@vger.kernel.org, Tony Luck <tony.luck@intel.com>,
	Fenghua Yu <fenghua.yu@intel.com>, Arnd Bergmann <arnd@arndb.de>,
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
	Daniel Vetter <daniel.vetter@ffwll.ch>,
	Souptick Joarder <jrdr.linux@gmail.com>,
	dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH] video: fbdev: atyfb: only use ioremap_uc() on i386 and ia64
Date: Mon, 11 Nov 2019 20:22:50 +0100	[thread overview]
Message-ID: <20191111192258.2234502-1-arnd@arndb.de> (raw)

ioremap_uc() is only meaningful on old x86-32 systems with the PAT
extension, and on ia64 with its slightly unconventional ioremap()
behavior, everywhere else this is the same as ioremap() anyway.

Change the only driver that still references ioremap_uc() to only do so
on x86-32/ia64 in order to allow removing that interface at some
point in the future for the other architectures.

On some architectures, ioremap_uc() just returns NULL, changing
the driver to call ioremap() means that they now have a chance
of working correctly.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/video/fbdev/aty/atyfb_base.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/video/fbdev/aty/atyfb_base.c b/drivers/video/fbdev/aty/atyfb_base.c
index 79d548746efd..bdbaca7200b2 100644
--- a/drivers/video/fbdev/aty/atyfb_base.c
+++ b/drivers/video/fbdev/aty/atyfb_base.c
@@ -3420,11 +3420,15 @@ static int atyfb_setup_generic(struct pci_dev *pdev, struct fb_info *info,
 	}
 
 	info->fix.mmio_start = raddr;
+#if defined(__i386__) || defined(__ia64__)
 	/*
 	 * By using strong UC we force the MTRR to never have an
 	 * effect on the MMIO region on both non-PAT and PAT systems.
 	 */
 	par->ati_regbase = ioremap_uc(info->fix.mmio_start, 0x1000);
+#else
+	par->ati_regbase = ioremap(info->fix.mmio_start, 0x1000);
+#endif
 	if (par->ati_regbase == NULL)
 		return -ENOMEM;
 
-- 
2.20.0

