Re: [PATCH 5/5] m68k: Add support for Svethlana

Hi Michael,

Thanks for your patch!

On Fri, 14 Aug 2026 at 05:18, Michael Schmitz <[email protected]> wrote:
> From: Miro Kropacek <[email protected]>
>
> The SuperVidel FPGA contains an OpenCore ethernet package. Add
> platform device data and other necessary definitions to support
> this device on Atari.
>
> The ethoc module must be enabled separately by the user.
>
> Signed-off-by: Miro Kropacek <[email protected]>
> Reviewed-by: Michael Schmitz <[email protected]>
> Link: https://lists.debian.org/debian-68k/2026/08/msg00000.html

Since you're now in the path to upstream, you should add your SoB here

> --- a/arch/m68k/atari/config.c
> +++ b/arch/m68k/atari/config.c
> @@ -34,6 +34,7 @@
>  #include <linux/platform_device.h>
>  #include <linux/usb/isp116x.h>
>  #include <linux/module.h>
> +#include <net/ethoc.h>
>
>  #include <asm/bootinfo.h>
>  #include <asm/bootinfo-atari.h>
> @@ -748,6 +749,62 @@ static struct platform_device *atari_ethernat_devices[] __initdata = {
>  };
>  #endif /* CONFIG_ATARI_ETHERNAT */
>
> +#ifdef CONFIG_ATARI_SVETHLANA
> +/*
> + * SVEthlana: OpenCores 10/100 Mbps Ethernet MAC in the SuperVidel FPGA,
> + * handled by the ethoc driver. Requires SuperVidel firmware version 10
> + * or newer (Ethernet DMA).
> + *
> + * The MAC can only DMA within the SuperVidel DDR RAM, so the packet
> + * buffers are carved out of the top of the DDR; the framebuffer lives
> + * at the bottom.
> + */
> +
> +#define ATARI_SVETHLANA_PHYS_ADDR      0x80012000
> +#define ATARI_SVETHLANA_IRQ            141     /* vector 0xc5 */
> +
> +#define ATARI_SV_VERSION_PHYS_ADDR     0x8001007c
> +#define ATARI_SV_DDR_END               0xa8000000
> +/* 128 packet buffers of 1536 bytes each, the maximum ethoc supports */
> +#define SVETHLANA_BUF_SIZE             (128 * 1536)
> +
> +static struct resource svethlana_resources[] = {
> +       [0] = {
> +               .name   = "ethoc-regs",
> +               .start  = ATARI_SVETHLANA_PHYS_ADDR,
> +               .end    = ATARI_SVETHLANA_PHYS_ADDR + 0x7ff,
> +               .flags  = IORESOURCE_MEM,
> +       },
> +       [1] = {
> +               .name   = "ethoc-buf",
> +               .start  = ATARI_SV_DDR_END - SVETHLANA_BUF_SIZE,
> +               .end    = ATARI_SV_DDR_END - 1,
> +               .flags  = IORESOURCE_MEM,
> +       },
> +       [2] = {
> +               .name   = "ethoc-irq",
> +               .start  = ATARI_SVETHLANA_IRQ,
> +               .end    = ATARI_SVETHLANA_IRQ,
> +               .flags  = IORESOURCE_IRQ,
> +       },
> +};
> +
> +static struct ethoc_platform_data svethlana_platform_data = {
> +       .phy_id         = -1,
> +       .big_endian     = true,

Does SVEthlana contain a unique MAC address?  Without this, you probably
get a different random MAC, and thus a different IP address from DHCP.

> +};
> +
> +static struct platform_device svethlana_device = {
> +       .name           = "ethoc",
> +       .id             = -1,
> +       .num_resources  = ARRAY_SIZE(svethlana_resources),
> +       .resource       = svethlana_resources,
> +       .dev            = {
> +               .platform_data  = &svethlana_platform_data,
> +       },
> +};
> +#endif /* CONFIG_ATARI_SVETHLANA */
> +
>  #ifdef CONFIG_ATARI_ETHERNEC
>  /*
>   * EtherNEC: RTL8019 (NE2000 compatible) Ethernet chipset,
> @@ -892,6 +949,20 @@ static int __init atari_platform_init(void)
>         }
>  #endif
>
> +#ifdef CONFIG_ATARI_SVETHLANA
> +       {
> +               void __iomem *sv_version;
> +
> +               sv_version = ioremap(ATARI_SV_VERSION_PHYS_ADDR, 4);
> +               if (sv_version) {
> +                       if (hwreg_present(sv_version) &&
> +                           (__raw_readl(sv_version) & 0x3ff) >= 10)
> +                               rv = platform_device_register(&svethlana_device);

This unconditionally writes to rv, potentially overwriting an error
code stored by a failed EtherNAT registration attempt.

> +                       iounmap(sv_version);
> +               }
> +       }
> +#endif
> +
>  #ifdef CONFIG_ATARI_ETHERNEC
>         {
>                 int error;

The rest LGTM.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds