[PATCH 6.5 18/88] fbdev: atyfb: only use ioremap_uc() on i386 and ia64

Greg Kroah-Hartman gregkh at linuxfoundation.org
Mon Nov 6 13:03:12 UTC 2023


6.5-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Arnd Bergmann <arnd at arndb.de>

[ Upstream commit c1a8d1d0edb71dec15c9649cb56866c71c1ecd9e ]

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 at arndb.de>
Signed-off-by: Baoquan He <bhe at redhat.com>
Reviewed-by: Luis Chamberlain <mcgrof at kernel.org>
Cc: Helge Deller <deller at gmx.de>
Cc: Thomas Zimmermann <tzimmermann at suse.de>
Cc: Christophe Leroy <christophe.leroy at csgroup.eu>
Cc: linux-fbdev at vger.kernel.org
Cc: dri-devel at lists.freedesktop.org
Signed-off-by: Helge Deller <deller at gmx.de>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 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 cba2b113b28b0..a73114c1c6918 100644
--- a/drivers/video/fbdev/aty/atyfb_base.c
+++ b/drivers/video/fbdev/aty/atyfb_base.c
@@ -3440,11 +3440,15 @@ 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;
 
-- 
2.42.0





More information about the dri-devel mailing list