[SeaBIOS] GeodeVGA global variable access

Christian Gmeiner christian.gmeiner at gmail.com
Sun Sep 16 19:38:52 CEST 2012


looks... fine... will comile it tomorrow in the office

---
Christian Gmeiner, MSc


2012/9/16 Kevin O'Connor <kevin at koconnor.net>:
> Hi Christian,
>
> I just noticed that a recent Geode patch introduced global variables
> that are accessed without GET_GLOBAL/SET_VGA macros.  This will cause
> random memory corruption.  Please see the patch below.
>
> -Kevin
>
>
> From ef7f73fa23e42953932920d39f729df82605b2a8 Mon Sep 17 00:00:00 2001
> From: Kevin O'Connor <kevin at koconnor.net>
> Date: Sun, 16 Sep 2012 13:24:30 -0400
> Subject: [PATCH] geodevga: Access global variables using GET_GLOBAL/SET_VGA
>  macros.
> To: seabios at seabios.org
>
> The vgabios runs in 16bit mode so all global variables must be
> accessed via macros.
>
> Signed-off-by: Kevin O'Connor <kevin at koconnor.net>
> ---
>  vgasrc/geodevga.c | 76 ++++++++++++++++++++++++++++---------------------------
>  1 file changed, 39 insertions(+), 37 deletions(-)
>
> diff --git a/vgasrc/geodevga.c b/vgasrc/geodevga.c
> index ed41be6..cf1382d 100644
> --- a/vgasrc/geodevga.c
> +++ b/vgasrc/geodevga.c
> @@ -86,55 +86,58 @@ static void geode_mem_mask(u32 addr, u32 off, u32 or)
>      );
>  }
>
> -/****************************************************************
> - * Helper functions
> - ****************************************************************/
> -
> -struct geode {
> -    u32 fb;
> -    u32 dc;
> -    u32 vp;
> -};
> -struct geode geode VAR16;
> +static u32 GeodeFB VAR16;
> +static u32 GeodeDC VAR16;
> +static u32 GeodeVP VAR16;
>
>  static u32 geode_dc_read(int reg)
>  {
> -    u32 val = geode_mem_read(geode.dc + reg);
> -    dprintf(4, "%s(0x%08x) = 0x%08x\n", __func__, geode.dc + reg, val);
> +    u32 val = geode_mem_read(GET_GLOBAL(GeodeDC) + reg);
> +    dprintf(4, "%s(0x%08x) = 0x%08x\n"
> +            , __func__, GET_GLOBAL(GeodeDC) + reg, val);
>      return val;
>  }
>
>  static void geode_dc_write(int reg, u32 val)
>  {
> -    dprintf(4, "%s(0x%08x, 0x%08x)\n", __func__, geode.dc + reg, val);
> -    geode_mem_mask(geode.dc + reg, ~0, val);
> +    dprintf(4, "%s(0x%08x, 0x%08x)\n"
> +            , __func__, GET_GLOBAL(GeodeDC) + reg, val);
> +    geode_mem_mask(GET_GLOBAL(GeodeDC) + reg, ~0, val);
>  }
>
>  static void geode_dc_mask(int reg, u32 off, u32 on)
>  {
> -    dprintf(4, "%s(0x%08x, 0x%08x, 0x%08x)\n", __func__, geode.dc + reg, off, on);
> -    geode_mem_mask(geode.dc + reg, off, on);
> +    dprintf(4, "%s(0x%08x, 0x%08x, 0x%08x)\n"
> +            , __func__, GET_GLOBAL(GeodeDC) + reg, off, on);
> +    geode_mem_mask(GET_GLOBAL(GeodeDC) + reg, off, on);
>  }
>
>  static u32 geode_vp_read(int reg)
>  {
> -    u32 val = geode_mem_read(geode.vp + reg);
> -    dprintf(4, "%s(0x%08x) = 0x%08x\n", __func__, geode.vp + reg, val);
> +    u32 val = geode_mem_read(GET_GLOBAL(GeodeVP) + reg);
> +    dprintf(4, "%s(0x%08x) = 0x%08x\n"
> +            , __func__, GET_GLOBAL(GeodeVP) + reg, val);
>      return val;
>  }
>
>  static void geode_vp_write(int reg, u32 val)
>  {
> -    dprintf(4, "%s(0x%08x, 0x%08x)\n", __func__, geode.vp + reg, val);
> -    geode_mem_mask(geode.vp + reg, ~0, val);
> +    dprintf(4, "%s(0x%08x, 0x%08x)\n"
> +            , __func__, GET_GLOBAL(GeodeVP) + reg, val);
> +    geode_mem_mask(GET_GLOBAL(GeodeVP) + reg, ~0, val);
>  }
>
>  static void geode_vp_mask(int reg, u32 off, u32 on)
>  {
> -    dprintf(4, "%s(0x%08x, 0x%08x, 0x%08x)\n", __func__, geode.vp + reg, off, on);
> -    geode_mem_mask(geode.vp + reg, off, on);
> +    dprintf(4, "%s(0x%08x, 0x%08x, 0x%08x)\n"
> +            , __func__, GET_GLOBAL(GeodeVP) + reg, off, on);
> +    geode_mem_mask(GET_GLOBAL(GeodeVP) + reg, off, on);
>  }
>
> +/****************************************************************
> + * Helper functions
> + ****************************************************************/
> +
>  static int legacyio_check(void)
>  {
>      int ret=0;
> @@ -199,10 +202,9 @@ static void dc_setup(void)
>      geode_dc_write(DC_CURS_ST_OFFSET, 0x0);
>
>      /* read fb-bar from pci, then point dc to the fb base */
> -    u32 dc_fb = geode_dc_read(DC_GLIU0_MEM_OFFSET);
> -    if (geode.fb != dc_fb) {
> -        geode_dc_write(DC_GLIU0_MEM_OFFSET, geode.fb);
> -    }
> +    u32 fb = GET_GLOBAL(GeodeFB);
> +    if (geode_dc_read(DC_GLIU0_MEM_OFFSET) != fb)
> +        geode_dc_write(DC_GLIU0_MEM_OFFSET, fb);
>
>      geode_dc_mask(DC_DISPLAY_CFG, ~DC_CFG_MSK, DC_GDEN|DC_TRUP);
>      geode_dc_write(DC_GENERAL_CFG, DC_VGAE);
> @@ -210,10 +212,10 @@ static void dc_setup(void)
>      geode_dc_write(DC_UNLOCK, DC_LOCK_LOCK);
>
>      u32 fb_size = framebuffer_size(); // in byte
> -    dprintf(1, "%d KB of video memory at 0x%08x\n", fb_size / 1024, geode.fb);
> +    dprintf(1, "%d KB of video memory at 0x%08x\n", fb_size / 1024, fb);
>
>      /* update VBE variables */
> -    SET_VGA(VBE_framebuffer, geode.fb);
> +    SET_VGA(VBE_framebuffer, fb);
>      SET_VGA(VBE_total_memory, fb_size / 1024 / 64); // number of 64K blocks
>  }
>
> @@ -335,16 +337,16 @@ int geodevga_init(void)
>      if (GET_GLOBAL(VgaBDF) < 0)
>          // Device should be at 00:01.1
>          SET_VGA(VgaBDF, pci_to_bdf(0, 1, 1));
> -
> +
>      // setup geode struct which is used for register access
> -    geode.fb = pci_config_readl(GET_GLOBAL(VgaBDF), PCI_BASE_ADDRESS_0);
> -    geode.dc = pci_config_readl(GET_GLOBAL(VgaBDF), PCI_BASE_ADDRESS_2);
> -    geode.vp = pci_config_readl(GET_GLOBAL(VgaBDF), PCI_BASE_ADDRESS_3);
> -
> -    dprintf(1, "fb addr: 0x%08x\n", geode.fb);
> -    dprintf(1, "dc addr: 0x%08x\n", geode.dc);
> -    dprintf(1, "vp addr: 0x%08x\n", geode.vp);
> -
> +    SET_VGA(GeodeFB, pci_config_readl(GET_GLOBAL(VgaBDF), PCI_BASE_ADDRESS_0));
> +    SET_VGA(GeodeDC, pci_config_readl(GET_GLOBAL(VgaBDF), PCI_BASE_ADDRESS_2));
> +    SET_VGA(GeodeVP, pci_config_readl(GET_GLOBAL(VgaBDF), PCI_BASE_ADDRESS_3));
> +
> +    dprintf(1, "fb addr: 0x%08x\n", GET_GLOBAL(GeodeFB));
> +    dprintf(1, "dc addr: 0x%08x\n", GET_GLOBAL(GeodeDC));
> +    dprintf(1, "vp addr: 0x%08x\n", GET_GLOBAL(GeodeVP));
> +
>      vp_setup();
>      dc_setup();
>
> --
> 1.7.11.4
>



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