This reverts commit a9e0cb67b7f4c485755659f9b764c38b5f970de4.

This breaks OVMF.  Reproducer: Just hit 'ESC' at early boot to enter
firmware setup.  OVMF wants switch from (default) 800x600 to 640x480 for
that, and this patch blocks it.

Cc: Hou Qiming <hqm03ster@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 hw/display/ramfb.c | 26 ++++----------------------
 1 file changed, 4 insertions(+), 22 deletions(-)

diff --git a/hw/display/ramfb.c b/hw/display/ramfb.c
index bd4746dc1768..9d41c2ad2868 100644
--- a/hw/display/ramfb.c
+++ b/hw/display/ramfb.c
@@ -31,7 +31,6 @@ struct RAMFBState {
     DisplaySurface *ds;
     uint32_t width, height;
     struct RAMFBCfg cfg;
-    bool locked;
 };
 
 static void ramfb_unmap_display_surface(pixman_image_t *image, void *unused)
@@ -72,25 +71,18 @@ static DisplaySurface *ramfb_create_display_surface(int width, int height,
 static void ramfb_fw_cfg_write(void *dev, off_t offset, size_t len)
 {
     RAMFBState *s = dev;
-    uint32_t fourcc, format, width, height;
+    uint32_t fourcc, format;
     hwaddr stride, addr;
 
-    width     = be32_to_cpu(s->cfg.width);
-    height    = be32_to_cpu(s->cfg.height);
+    s->width  = be32_to_cpu(s->cfg.width);
+    s->height = be32_to_cpu(s->cfg.height);
     stride    = be32_to_cpu(s->cfg.stride);
     fourcc    = be32_to_cpu(s->cfg.fourcc);
     addr      = be64_to_cpu(s->cfg.addr);
     format    = qemu_drm_format_to_pixman(fourcc);
 
     fprintf(stderr, "%s: %dx%d @ 0x%" PRIx64 "\n", __func__,
-            width, height, addr);
-    if (s->locked) {
-        fprintf(stderr, "%s: resolution locked, change rejected\n", __func__);
-        return;
-    }
-    s->locked = true;
-    s->width = width;
-    s->height = height;
+            s->width, s->height, addr);
     s->ds = ramfb_create_display_surface(s->width, s->height,
                                          format, stride, addr);
 }
@@ -110,13 +102,6 @@ void ramfb_display_update(QemuConsole *con, RAMFBState *s)
     dpy_gfx_update_full(con);
 }
 
-static void ramfb_reset(void *opaque)
-{
-    RAMFBState *s = (RAMFBState *)opaque;
-    s->locked = false;
-    memset(&s->cfg, 0, sizeof(s->cfg));
-}
-
 RAMFBState *ramfb_setup(Error **errp)
 {
     FWCfgState *fw_cfg = fw_cfg_find();
@@ -129,12 +114,9 @@ RAMFBState *ramfb_setup(Error **errp)
 
     s = g_new0(RAMFBState, 1);
 
-    s->locked = false;
-
     rom_add_vga("vgabios-ramfb.bin");
     fw_cfg_add_file_callback(fw_cfg, "etc/ramfb",
                              NULL, ramfb_fw_cfg_write, s,
                              &s->cfg, sizeof(s->cfg), false);
-    qemu_register_reset(ramfb_reset, s);
     return s;
 }
-- 
2.18.2

On 04/22/20 12:02, Gerd Hoffmann wrote:
> This reverts commit a9e0cb67b7f4c485755659f9b764c38b5f970de4.
> 
> This breaks OVMF.  Reproducer: Just hit 'ESC' at early boot to enter
> firmware setup.  OVMF wants switch from (default) 800x600 to 640x480 for
> that, and this patch blocks it.
> 
> Cc: Hou Qiming <hqm03ster@gmail.com>
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  hw/display/ramfb.c | 26 ++++----------------------
>  1 file changed, 4 insertions(+), 22 deletions(-)

(1) I've verified that, after applying patches #1 and #2 in this series,
the resultant state of "hw/display/ramfb.c" matches the one at
a9e0cb67b7f4^ (note the caret), modulo:

- commit 71e8a9158558 ("Include sysemu/reset.h a lot less", 2019-08-16), and

- commit 85eb7c18ee39 ("Let cpu_[physical]_memory() calls pass a boolean
'is_write' argument", 2020-02-20).

So:

Reviewed-by: Laszlo Ersek <lersek@redhat.com>

(2) I've also tested this patch (i.e., built QEMU with patches #1 and #2
applied -- patch #1 is needed for context --, and entered the OVMF Setup
TUI while using ramfb).

Tested-by: Laszlo Ersek <lersek@redhat.com>

Thanks!
Laszlo

> diff --git a/hw/display/ramfb.c b/hw/display/ramfb.c
> index bd4746dc1768..9d41c2ad2868 100644
> --- a/hw/display/ramfb.c
> +++ b/hw/display/ramfb.c
> @@ -31,7 +31,6 @@ struct RAMFBState {
>      DisplaySurface *ds;
>      uint32_t width, height;
>      struct RAMFBCfg cfg;
> -    bool locked;
>  };
>  
>  static void ramfb_unmap_display_surface(pixman_image_t *image, void *unused)
> @@ -72,25 +71,18 @@ static DisplaySurface *ramfb_create_display_surface(int width, int height,
>  static void ramfb_fw_cfg_write(void *dev, off_t offset, size_t len)
>  {
>      RAMFBState *s = dev;
> -    uint32_t fourcc, format, width, height;
> +    uint32_t fourcc, format;
>      hwaddr stride, addr;
>  
> -    width     = be32_to_cpu(s->cfg.width);
> -    height    = be32_to_cpu(s->cfg.height);
> +    s->width  = be32_to_cpu(s->cfg.width);
> +    s->height = be32_to_cpu(s->cfg.height);
>      stride    = be32_to_cpu(s->cfg.stride);
>      fourcc    = be32_to_cpu(s->cfg.fourcc);
>      addr      = be64_to_cpu(s->cfg.addr);
>      format    = qemu_drm_format_to_pixman(fourcc);
>  
>      fprintf(stderr, "%s: %dx%d @ 0x%" PRIx64 "\n", __func__,
> -            width, height, addr);
> -    if (s->locked) {
> -        fprintf(stderr, "%s: resolution locked, change rejected\n", __func__);
> -        return;
> -    }
> -    s->locked = true;
> -    s->width = width;
> -    s->height = height;
> +            s->width, s->height, addr);
>      s->ds = ramfb_create_display_surface(s->width, s->height,
>                                           format, stride, addr);
>  }
> @@ -110,13 +102,6 @@ void ramfb_display_update(QemuConsole *con, RAMFBState *s)
>      dpy_gfx_update_full(con);
>  }
>  
> -static void ramfb_reset(void *opaque)
> -{
> -    RAMFBState *s = (RAMFBState *)opaque;
> -    s->locked = false;
> -    memset(&s->cfg, 0, sizeof(s->cfg));
> -}
> -
>  RAMFBState *ramfb_setup(Error **errp)
>  {
>      FWCfgState *fw_cfg = fw_cfg_find();
> @@ -129,12 +114,9 @@ RAMFBState *ramfb_setup(Error **errp)
>  
>      s = g_new0(RAMFBState, 1);
>  
> -    s->locked = false;
> -
>      rom_add_vga("vgabios-ramfb.bin");
>      fw_cfg_add_file_callback(fw_cfg, "etc/ramfb",
>                               NULL, ramfb_fw_cfg_write, s,
>                               &s->cfg, sizeof(s->cfg), false);
> -    qemu_register_reset(ramfb_reset, s);
>      return s;
>  }
>