| Message ID | 20210113145009.1272040-15-lee.jones@linaro.org (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | Rid W=1 warnings from Video | expand |
Hi, If I remember well, the removed lines have to do with the VGA/accelerator mode of the chip. The current driver always runs the chip in accelerator mode. Suppose you would want to support high resolution hardware text modes with the driver (fbdev bpp=0), then you would need to switch the chip into VGA mode mode and then the removed lines become relevant. I did some experiments with this when I was working on the driver, but because the documentation was silent about the behaviour of extended CRTC registers in VGA mode, I failed to make hardware text modes to work properly. The #if 0 was there so code was already there in case me or someone else would pick it up again. Best regards, Daniël Mantione Op Wed, 13 Jan 2021, schreef Lee Jones: > Fixes the following W=1 kernel build warning(s): > > drivers/video/fbdev/aty/mach64_ct.c: In function ‘aty_init_pll_ct’: > drivers/video/fbdev/aty/mach64_ct.c:405:46: warning: variable ‘vga_dsp_on_off’ set but not used [-Wunused-but-set-variable] > drivers/video/fbdev/aty/mach64_ct.c:405:30: warning: variable ‘vga_dsp_config’ set but not used [-Wunused-but-set-variable] > drivers/video/fbdev/aty/mach64_ct.c:405:18: warning: variable ‘dsp_on_off’ set but not used [-Wunused-but-set-variable] > > Cc: daniel.mantione@freepascal.org > Cc: dri-devel@lists.freedesktop.org > Cc: linux-fbdev@vger.kernel.org > Signed-off-by: Lee Jones <lee.jones@linaro.org> > --- > drivers/video/fbdev/aty/mach64_ct.c | 19 ++----------------- > 1 file changed, 2 insertions(+), 17 deletions(-) > > diff --git a/drivers/video/fbdev/aty/mach64_ct.c b/drivers/video/fbdev/aty/mach64_ct.c > index f87cc81f4fa2b..23eececa1e9d7 100644 > --- a/drivers/video/fbdev/aty/mach64_ct.c > +++ b/drivers/video/fbdev/aty/mach64_ct.c > @@ -402,7 +402,7 @@ static int aty_init_pll_ct(const struct fb_info *info, union aty_pll *pll) > struct atyfb_par *par = (struct atyfb_par *) info->par; > u8 mpost_div, xpost_div, sclk_post_div_real; > u32 q, memcntl, trp; > - u32 dsp_config, dsp_on_off, vga_dsp_config, vga_dsp_on_off; > + u32 dsp_config; > #ifdef DEBUG > int pllmclk, pllsclk; > #endif > @@ -488,25 +488,10 @@ static int aty_init_pll_ct(const struct fb_info *info, union aty_pll *pll) > > /* Allow BIOS to override */ > dsp_config = aty_ld_le32(DSP_CONFIG, par); > - dsp_on_off = aty_ld_le32(DSP_ON_OFF, par); > - vga_dsp_config = aty_ld_le32(VGA_DSP_CONFIG, par); > - vga_dsp_on_off = aty_ld_le32(VGA_DSP_ON_OFF, par); > > if (dsp_config) > pll->ct.dsp_loop_latency = (dsp_config & DSP_LOOP_LATENCY) >> 16; > -#if 0 > - FIXME: is it relevant for us? > - if ((!dsp_on_off && !M64_HAS(RESET_3D)) || > - ((dsp_on_off == vga_dsp_on_off) && > - (!dsp_config || !((dsp_config ^ vga_dsp_config) & DSP_XCLKS_PER_QW)))) { > - vga_dsp_on_off &= VGA_DSP_OFF; > - vga_dsp_config &= VGA_DSP_XCLKS_PER_QW; > - if (ATIDivide(vga_dsp_on_off, vga_dsp_config, 5, 1) > 24) > - pll->ct.fifo_size = 32; > - else > - pll->ct.fifo_size = 24; > - } > -#endif > + > /* Exit if the user does not want us to tamper with the clock > rates of her chip. */ > if (par->mclk_per == 0) { > -- > 2.25.1 >
On Wed, 13 Jan 2021, Daniël Mantione wrote: > Hi, > > If I remember well, the removed lines have to do with the VGA/accelerator > mode of the chip. The current driver always runs the chip in accelerator > mode. Suppose you would want to support high resolution hardware text modes > with the driver (fbdev bpp=0), then you would need to switch the chip into > VGA mode mode and then the removed lines become relevant. > > I did some experiments with this when I was working on the driver, but > because the documentation was silent about the behaviour of extended CRTC > registers in VGA mode, I failed to make hardware text modes to work > properly. > > The #if 0 was there so code was already there in case me or someone else > would pick it up again. This code has been commented out for *at least* 16 years. Probably time to let it go. :) > Best regards, > > Daniël Mantione > > Op Wed, 13 Jan 2021, schreef Lee Jones: > > > Fixes the following W=1 kernel build warning(s): > > > > drivers/video/fbdev/aty/mach64_ct.c: In function ‘aty_init_pll_ct’: > > drivers/video/fbdev/aty/mach64_ct.c:405:46: warning: variable ‘vga_dsp_on_off’ set but not used [-Wunused-but-set-variable] > > drivers/video/fbdev/aty/mach64_ct.c:405:30: warning: variable ‘vga_dsp_config’ set but not used [-Wunused-but-set-variable] > > drivers/video/fbdev/aty/mach64_ct.c:405:18: warning: variable ‘dsp_on_off’ set but not used [-Wunused-but-set-variable] > > > > Cc: daniel.mantione@freepascal.org > > Cc: dri-devel@lists.freedesktop.org > > Cc: linux-fbdev@vger.kernel.org > > Signed-off-by: Lee Jones <lee.jones@linaro.org> > > --- > > drivers/video/fbdev/aty/mach64_ct.c | 19 ++----------------- > > 1 file changed, 2 insertions(+), 17 deletions(-) > > > > diff --git a/drivers/video/fbdev/aty/mach64_ct.c b/drivers/video/fbdev/aty/mach64_ct.c > > index f87cc81f4fa2b..23eececa1e9d7 100644 > > --- a/drivers/video/fbdev/aty/mach64_ct.c > > +++ b/drivers/video/fbdev/aty/mach64_ct.c > > @@ -402,7 +402,7 @@ static int aty_init_pll_ct(const struct fb_info *info, union aty_pll *pll) > > struct atyfb_par *par = (struct atyfb_par *) info->par; > > u8 mpost_div, xpost_div, sclk_post_div_real; > > u32 q, memcntl, trp; > > - u32 dsp_config, dsp_on_off, vga_dsp_config, vga_dsp_on_off; > > + u32 dsp_config; > > #ifdef DEBUG > > int pllmclk, pllsclk; > > #endif > > @@ -488,25 +488,10 @@ static int aty_init_pll_ct(const struct fb_info *info, union aty_pll *pll) > > > > /* Allow BIOS to override */ > > dsp_config = aty_ld_le32(DSP_CONFIG, par); > > - dsp_on_off = aty_ld_le32(DSP_ON_OFF, par); > > - vga_dsp_config = aty_ld_le32(VGA_DSP_CONFIG, par); > > - vga_dsp_on_off = aty_ld_le32(VGA_DSP_ON_OFF, par); > > > > if (dsp_config) > > pll->ct.dsp_loop_latency = (dsp_config & DSP_LOOP_LATENCY) >> 16; > > -#if 0 > > - FIXME: is it relevant for us? > > - if ((!dsp_on_off && !M64_HAS(RESET_3D)) || > > - ((dsp_on_off == vga_dsp_on_off) && > > - (!dsp_config || !((dsp_config ^ vga_dsp_config) & DSP_XCLKS_PER_QW)))) { > > - vga_dsp_on_off &= VGA_DSP_OFF; > > - vga_dsp_config &= VGA_DSP_XCLKS_PER_QW; > > - if (ATIDivide(vga_dsp_on_off, vga_dsp_config, 5, 1) > 24) > > - pll->ct.fifo_size = 32; > > - else > > - pll->ct.fifo_size = 24; > > - } > > -#endif > > + > > /* Exit if the user does not want us to tamper with the clock > > rates of her chip. */ > > if (par->mclk_per == 0) {
diff --git a/drivers/video/fbdev/aty/mach64_ct.c b/drivers/video/fbdev/aty/mach64_ct.c index f87cc81f4fa2b..23eececa1e9d7 100644 --- a/drivers/video/fbdev/aty/mach64_ct.c +++ b/drivers/video/fbdev/aty/mach64_ct.c @@ -402,7 +402,7 @@ static int aty_init_pll_ct(const struct fb_info *info, union aty_pll *pll) struct atyfb_par *par = (struct atyfb_par *) info->par; u8 mpost_div, xpost_div, sclk_post_div_real; u32 q, memcntl, trp; - u32 dsp_config, dsp_on_off, vga_dsp_config, vga_dsp_on_off; + u32 dsp_config; #ifdef DEBUG int pllmclk, pllsclk; #endif @@ -488,25 +488,10 @@ static int aty_init_pll_ct(const struct fb_info *info, union aty_pll *pll) /* Allow BIOS to override */ dsp_config = aty_ld_le32(DSP_CONFIG, par); - dsp_on_off = aty_ld_le32(DSP_ON_OFF, par); - vga_dsp_config = aty_ld_le32(VGA_DSP_CONFIG, par); - vga_dsp_on_off = aty_ld_le32(VGA_DSP_ON_OFF, par); if (dsp_config) pll->ct.dsp_loop_latency = (dsp_config & DSP_LOOP_LATENCY) >> 16; -#if 0 - FIXME: is it relevant for us? - if ((!dsp_on_off && !M64_HAS(RESET_3D)) || - ((dsp_on_off == vga_dsp_on_off) && - (!dsp_config || !((dsp_config ^ vga_dsp_config) & DSP_XCLKS_PER_QW)))) { - vga_dsp_on_off &= VGA_DSP_OFF; - vga_dsp_config &= VGA_DSP_XCLKS_PER_QW; - if (ATIDivide(vga_dsp_on_off, vga_dsp_config, 5, 1) > 24) - pll->ct.fifo_size = 32; - else - pll->ct.fifo_size = 24; - } -#endif + /* Exit if the user does not want us to tamper with the clock rates of her chip. */ if (par->mclk_per == 0) {
Fixes the following W=1 kernel build warning(s): drivers/video/fbdev/aty/mach64_ct.c: In function ‘aty_init_pll_ct’: drivers/video/fbdev/aty/mach64_ct.c:405:46: warning: variable ‘vga_dsp_on_off’ set but not used [-Wunused-but-set-variable] drivers/video/fbdev/aty/mach64_ct.c:405:30: warning: variable ‘vga_dsp_config’ set but not used [-Wunused-but-set-variable] drivers/video/fbdev/aty/mach64_ct.c:405:18: warning: variable ‘dsp_on_off’ set but not used [-Wunused-but-set-variable] Cc: daniel.mantione@freepascal.org Cc: dri-devel@lists.freedesktop.org Cc: linux-fbdev@vger.kernel.org Signed-off-by: Lee Jones <lee.jones@linaro.org> --- drivers/video/fbdev/aty/mach64_ct.c | 19 ++----------------- 1 file changed, 2 insertions(+), 17 deletions(-)