Hi Hans On Tue, Jun 26, 2018 at 3:38 PM, Michael Nazzareno Trimarchi <michael@xxxxxxxxxxxxxxxxxxxx> wrote: > Hi > > On Tue, Jun 26, 2018 at 3:36 PM, Hans de Goede <hdegoede@xxxxxxxxxx> wrote: >> Hi, >> >> >> On 26-06-18 15:29, Michael Nazzareno Trimarchi wrote: >>> >>> Hi >>> >>> to be more specific >>> >>> On Tue, Jun 26, 2018 at 3:06 PM, Michael Nazzareno Trimarchi >>> <michael@xxxxxxxxxxxxxxxxxxxx> wrote: >>>> >>>> Hi >>>> >>>> On Tue., 26 Jun. 2018, 12:01 pm Hans de Goede, <hdegoede@xxxxxxxxxx> >>>> wrote: >>>>> >>>>> >>>>> Hi, >>>>> >>>>> On 25-06-18 15:29, Michael Nazzareno Trimarchi wrote: >>>>>> >>>>>> Hi Hans >>>>>> >>>>>> In order to let it even registered the simplefb I have added this >>>>>> change. According on what I understand >>>>>> from the code seems that this is the way to acquire memory with the >>>>>> correct attribute >>>>>> >>>>>> diff --git a/drivers/video/fbdev/simplefb.c >>>>>> b/drivers/video/fbdev/simplefb.c >>>>>> index a3c44ec..7e61ce3 100644 >>>>>> --- a/drivers/video/fbdev/simplefb.c >>>>>> +++ b/drivers/video/fbdev/simplefb.c >>>>>> @@ -466,8 +466,8 @@ static int simplefb_probe(struct platform_device >>>>>> *pdev) >>>>>> >>>>>> info->fbops = &simplefb_ops; >>>>>> info->flags = FBINFO_DEFAULT | FBINFO_MISC_FIRMWARE; >>>>>> - info->screen_base = ioremap_wc(info->fix.smem_start, >>>>>> - info->fix.smem_len); >>>>>> + info->screen_base = arch_memremap_wb(info->fix.smem_start, >>>>>> + info->fix.smem_len); >>>>> >>>>> >>>>> I'm not sure why you need this? wb certainly is not optimal >>>>> for a framebuffer, the existing wc mapping is really what you >>>>> want. >>>>> >>>> >>>> Well in this way raise a WARN and get a nice NULL on memory remap on >>>> imx6ull >>>> SoC >>>> >>> >>> [ 0.397484] WARNING: CPU: 0 PID: 1 at arch/arm/mm/ioremap.c:303 >>> __arm_ioremap_pfn_caller+0x80/0x1cc >> >> >> >> This is causes by a mismatch in memory attributes, which means the >> memory is already mapped by the kernel as regular RAM and may >> already be used for other purposes by the kernel! >> >> Memory used by a simplefb framebuffer must be reserved by the >> bootloader, so that it does not get used by the kernel as regular >> RAM. See e.g.: >> >> http://git.denx.de/?p=u-boot.git;a=blob;f=drivers/video/sunxi/sunxi_display.c >> >> Near the end of the file where the framebuffer RAM gets excluded from >> the memory-range reported to the kernel as usable RAM. Note this relies >> on the u-boot sunxi video code putting the framebuffer at the end of the >> RAM. + aliases { + display0 = &lcdif; + }; + + reserved-memory { + #address-cells = <1>; + #size-cells = <1>; + ranges; + + display_reserved: framebuffer@86fd6080 { + reg = <0x86fd6080 (480 * 272 *4)>; + }; + This should do the trick but I have still the same problem on memory type. Any idea? + linux,cma { + compatible = "shared-dma-pool"; + reusable; + size = <0x1000000>; + linux,cma-default; + }; + }; + + chosen { + #address-cells = <1>; + #size-cells = <1>; + ranges; + + stdout-path = &uart1; + framebuffer0: framebuffer@86fd6080 { + compatible = "simple-framebuffer"; + reg = <0x86fd6080 (480 * 272 * 4)>; Here I try to use the same. I will create in uboot a dynamic way to track down. I think that we can even add to the simple buffer a way to get hand of reserved region automatically Michael + width = <480>; + height = <272>; + stride = <(480 * 4)>; + format = "a8r8g8b8"; + clocks = <&clks IMX6UL_CLK_LCDIF_PIX>, + <&clks IMX6UL_CLK_LCDIF_APB>, + <&clks IMX6UL_CLK_DUMMY>, + <&clks IMX6UL_CLK_GPIO3>, + <&clks IMX6UL_CLK_GPIO4>; + nshut-supply = <®_lcd_nshut>; + nreset-supply = <®_lcd_nreset>; + display = <&lcdif>; + status = "okay"; + }; >> > > Thank you very much for this lesson ;). I will try to document better > after my tour ;) > > Michael > >> Regards, >> >> Hans > > > > -- > | Michael Nazzareno Trimarchi Amarula Solutions BV | > | COO - Founder Cruquiuskade 47 | > | +31(0)851119172 Amsterdam 1018 AM NL | > | [`as] http://www.amarulasolutions.com | -- | Michael Nazzareno Trimarchi Amarula Solutions BV | | COO - Founder Cruquiuskade 47 | | +31(0)851119172 Amsterdam 1018 AM NL | | [`as] http://www.amarulasolutions.com | -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
