From:   Baoquan He <bhe@redhat.com>
To:     linux-kernel@vger.kernel.org
Cc:     linux-arch@vger.kernel.org, linux-mm@kvack.org, arnd@arndb.de,
        mpe@ellerman.id.au, geert@linux-m68k.org, mcgrof@kernel.org,
        hch@infradead.org, Baoquan He <bhe@redhat.com>,
        Helge Deller <deller@gmx.de>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
        linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org
Subject: [PATCH v4 1/4] video: fbdev: atyfb: only use ioremap_uc() on i386 and ia64
Date:   Wed,  8 Mar 2023 21:07:07 +0800
Message-Id: <20230308130710.368085-2-bhe@redhat.com>
In-Reply-To: <20230308130710.368085-1-bhe@redhat.com>
References: <20230308130710.368085-1-bhe@redhat.com>
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From: Arnd Bergmann <arnd@arndb.de>

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>
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.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 b02e4e645035..6553c71b113f 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;
 
-- 
2.34.1