From: Jan Beulich <jbeulich@suse.com>
Date: Fri, 18 Feb 2022 13:45:14 +0000 (+0100)
Subject: video/vesa: drop "vesa-mtrr" command line option
X-Git-Tag: archive/raspbian/4.17.0-1+rpi1^2~33^2~1010
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=6ba701064227c6a4baa64d377e1ad869452f7fb6;p=xen.git

video/vesa: drop "vesa-mtrr" command line option

Now that we use ioremap_wc() for mapping the frame buffer, there's no
need for this option anymore. As noted in the change introducing the
use of ioremap_wc(), mtrr_add() didn't work in certain cases anyway.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
---

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6c0cd88cdf..9f596eac3e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ## [unstable UNRELEASED](https://xenbits.xen.org/gitweb/?p=xen.git;a=shortlog;h=staging) - TBD
 
+### Removed / support downgraded
+ - dropped support for the (x86-only) "vesa-mtrr" command line option
+
 ## [4.16.0](https://xenbits.xen.org/gitweb/?p=xen.git;a=shortlog;h=staging) - 2021-12-02
 
 ### Removed
diff --git a/docs/misc/xen-command-line.pandoc b/docs/misc/xen-command-line.pandoc
index 1ca817f5e1..a64aa5e841 100644
--- a/docs/misc/xen-command-line.pandoc
+++ b/docs/misc/xen-command-line.pandoc
@@ -2492,9 +2492,6 @@ cache-warming. 1ms (1000) has been measured as a good value.
 ### vesa-map
 > `= <integer>`
 
-### vesa-mtrr
-> `= <integer>`
-
 ### vesa-ram
 > `= <integer>`
 
diff --git a/xen/arch/x86/include/asm/setup.h b/xen/arch/x86/include/asm/setup.h
index 7dc03b6b8d..21037b7f31 100644
--- a/xen/arch/x86/include/asm/setup.h
+++ b/xen/arch/x86/include/asm/setup.h
@@ -28,10 +28,8 @@ void init_IRQ(void);
 
 #ifdef CONFIG_VIDEO
 void vesa_init(void);
-void vesa_mtrr_init(void);
 #else
 static inline void vesa_init(void) {};
-static inline void vesa_mtrr_init(void) {};
 #endif
 
 int construct_dom0(
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index 624b53ded4..2f6e10d0cf 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -1808,8 +1808,6 @@ void __init noreturn __start_xen(unsigned long mbi_p)
 
     local_irq_enable();
 
-    vesa_mtrr_init();
-
     early_msi_init();
 
     iommu_setup();    /* setup iommu if available */
diff --git a/xen/drivers/video/vesa.c b/xen/drivers/video/vesa.c
index b9bdfc1670..5cc37f0171 100644
--- a/xen/drivers/video/vesa.c
+++ b/xen/drivers/video/vesa.c
@@ -145,38 +145,6 @@ void __init vesa_init(void)
     video_puts = lfb_redraw_puts;
 }
 
-#include <asm/mtrr.h>
-
-static unsigned int vesa_mtrr;
-integer_param("vesa-mtrr", vesa_mtrr);
-
-void __init vesa_mtrr_init(void)
-{
-    static const int mtrr_types[] = {
-        0, MTRR_TYPE_UNCACHABLE, MTRR_TYPE_WRBACK,
-        MTRR_TYPE_WRCOMB, MTRR_TYPE_WRTHROUGH };
-    unsigned int size_total;
-    int rc, type;
-
-    if ( !lfb || (vesa_mtrr == 0) || (vesa_mtrr >= ARRAY_SIZE(mtrr_types)) )
-        return;
-
-    type = mtrr_types[vesa_mtrr];
-    if ( !type )
-        return;
-
-    /* Find the largest power-of-two */
-    size_total = vram_total;
-    while ( size_total & (size_total - 1) )
-        size_total &= size_total - 1;
-
-    /* Try and find a power of two to add */
-    do {
-        rc = mtrr_add(lfb_base(), size_total, type, 1);
-        size_total >>= 1;
-    } while ( (size_total >= PAGE_SIZE) && (rc == -EINVAL) );
-}
-
 static void lfb_flush(void)
 {
     __asm__ __volatile__ ("sfence" : : : "memory");