On Wed, Apr 27, 2022 at 06:47:53AM -0700, Saurabh Sengar wrote:
> This patch fixes a bug where GEN1 VMs doesn't allow resolutions greater
> than 64 MB size (eg 7680x4320). Unnecessary PCI check limits Gen1 VRAM
> to legacy PCI BAR size only (ie 64MB). Thus any, resolution requesting
> greater then 64MB (eg 7680x4320) would fail. MMIO region assigning this
> memory shouldn't be limited by PCI bar size.
>
> Signed-off-by: Saurabh Sengar <ssen...@linux.microsoft.com>
> ---
> drivers/video/fbdev/hyperv_fb.c | 19 +------------------
> 1 file changed, 1 insertion(+), 18 deletions(-)
>
> diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
> index c8e0ea2..58c304a 100644
> --- a/drivers/video/fbdev/hyperv_fb.c
> +++ b/drivers/video/fbdev/hyperv_fb.c
> @@ -1009,7 +1009,6 @@ static int hvfb_getmem(struct hv_device *hdev, struct
> fb_info *info)
> struct pci_dev *pdev = NULL;
> void __iomem *fb_virt;
> int gen2vm = efi_enabled(EFI_BOOT);
> - resource_size_t pot_start, pot_end;
> phys_addr_t paddr;
> int ret;
>
> @@ -1060,23 +1059,7 @@ static int hvfb_getmem(struct hv_device *hdev, struct
> fb_info *info)
> dio_fb_size =
> screen_width * screen_height * screen_depth / 8;
>
> - if (gen2vm) {
> - pot_start = 0;
> - pot_end = -1;
> - } else {
> - if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM) ||
> - pci_resource_len(pdev, 0) < screen_fb_size) {
> - pr_err("Resource not available or (0x%lx < 0x%lx)\n",
> - (unsigned long) pci_resource_len(pdev, 0),
> - (unsigned long) screen_fb_size);
> - goto err1;
This restriction has been in place since day 1. Haiyang, you wrote this
driver. Can you comment on whether this change here is sensible?
Thanks,
Wei.
> - }
> -
> - pot_end = pci_resource_end(pdev, 0);
> - pot_start = pot_end - screen_fb_size + 1;
> - }
> -
> - ret = vmbus_allocate_mmio(&par->mem, hdev, pot_start, pot_end,
> + ret = vmbus_allocate_mmio(&par->mem, hdev, 0, -1,
> screen_fb_size, 0x100000, true);
> if (ret != 0) {
> pr_err("Unable to allocate framebuffer memory\n");
> --
> 1.8.3.1
>
