[PATCH net-next v3] net: ethernet: stmmac: dwmac-rk: Make the clk_phy could be used for external phy

[Marek Szyprowski]

On 15.08.2025 04:35, Chaoyi Chen wrote:
> From: Chaoyi Chen <chaoyi.chen at rock-chips.com>
>
> For external phy, clk_phy should be optional, and some external phy
> need the clock input from clk_phy. This patch adds support for setting
> clk_phy for external phy.
>
> Signed-off-by: David Wu <david.wu at rock-chips.com>
> Signed-off-by: Chaoyi Chen <chaoyi.chen at rock-chips.com>
> ---
>
> Changes in v3:
> - Link to V2: https://lore.kernel.org/netdev/20250812012127.197-1-kernel@airkyi.com/
> - Rebase to net-next/main
>
> Changes in v2:
> - Link to V1: https://lore.kernel.org/netdev/20250806011405.115-1-kernel@airkyi.com/
> - Remove get clock frequency from DT prop
>
>   drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c | 11 +++++++----
>   1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> index ac8288301994..5d921e62c2f5 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> @@ -1412,12 +1412,15 @@ static int rk_gmac_clk_init(struct plat_stmmacenet_data *plat)
>   		clk_set_rate(plat->stmmac_clk, 50000000);
>   	}
>   
> -	if (plat->phy_node && bsp_priv->integrated_phy) {
> +	if (plat->phy_node) {
>   		bsp_priv->clk_phy = of_clk_get(plat->phy_node, 0);
>   		ret = PTR_ERR_OR_ZERO(bsp_priv->clk_phy);
> -		if (ret)
> -			return dev_err_probe(dev, ret, "Cannot get PHY clock\n");
> -		clk_set_rate(bsp_priv->clk_phy, 50000000);
> +		/* If it is not integrated_phy, clk_phy is optional */
> +		if (bsp_priv->integrated_phy) {
> +			if (ret)
> +				return dev_err_probe(dev, ret, "Cannot get PHY clock\n");
> +			clk_set_rate(bsp_priv->clk_phy, 50000000);
> +		}
>   	}
>   
>   	return 0;

The above change lacks the following check ingmac_clk_enable(): if (!bsp_priv->integrated_phy) return 0;

Otherwise it blows on machines with integrated PHY, like Hardkernel's Odroid-M1 (RK3568 based):

rk_gmac-dwmac fe2a0000.ethernet: IRQ eth_lpi not found
rk_gmac-dwmac fe2a0000.ethernet: IRQ sfty not found
rk_gmac-dwmac fe2a0000.ethernet: clock input or output? (output).
rk_gmac-dwmac fe2a0000.ethernet: TX delay(0x4f).
rk_gmac-dwmac fe2a0000.ethernet: RX delay(0x2d).
rk_gmac-dwmac fe2a0000.ethernet: integrated PHY? (no).
Unable to handle kernel paging request at virtual address fffffffffffffffe
Mem abort info:
   ESR = 0x0000000096000006
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
   FSC = 0x06: level 2 translation fault
Data abort info:
   ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000
   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
swapper pgtable: 4k pages, 48-bit VAs, pgdp=000000000249e000
[fffffffffffffffe] pgd=0000000000000000, p4d=000000000376f403, pud=0000000003770403, pmd=0000000000000000
Internal error: Oops: 0000000096000006 [#1]  SMP
Modules linked in: snd_soc_rockchip_i2s_tdm snd_soc_rk817 snd_soc_core snd_compress snd_pcm_dmaengine rockchip_thermal snd_pcm dwmac_rk(+) hantro_vpu rockchip_saradc industrialio_triggered_buffer kfifo_buf stmmac_platform rockchip_rga v4l2_vp9 stmmac spi_rockchip_sfc(+) v4l2_h264 snd_timer pcs_xpcs rockchipdrm(+) videobuf2_dma_sg v4l2_jpeg rk805_pwrkey v4l2_mem2mem videobuf2_dma_contig dw_hdmi_qp rockchip_dfi rk817_charger videobuf2_memops analogix_dp videobuf2_v4l2 dw_mipi_dsi panfrost snd rtc_rk808 drm_dp_aux_bus videodev drm_shmem_helper soundcore dw_hdmi videobuf2_common drm_display_helper mc gpu_sched ahci_dwc ipv6
CPU: 3 UID: 0 PID: 154 Comm: systemd-udevd Not tainted 6.17.0-rc1+ #10875 PREEMPT
Hardware name: Hardkernel ODROID-M1 (DT)
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : clk_prepare+0x18/0x44
lr : gmac_clk_enable+0xf8/0x188 [dwmac_rk]
..
Call trace:
  clk_prepare+0x18/0x44 (P)
  gmac_clk_enable+0xf8/0x188 [dwmac_rk]
  rk_gmac_powerup+0x4c/0x1f0 [dwmac_rk]
  rk_gmac_probe+0x3b4/0x5c8 [dwmac_rk]
  platform_probe+0x5c/0xac
  really_probe+0xbc/0x298
  __driver_probe_device+0x78/0x12c
  driver_probe_device+0x40/0x164
  __driver_attach+0x9c/0x1ac
  bus_for_each_dev+0x74/0xd0
  driver_attach+0x24/0x30
  bus_add_driver+0xe4/0x208
  driver_register+0x60/0x128
  __platform_driver_register+0x24/0x30
  rk_gmac_dwmac_driver_init+0x20/0x1000 [dwmac_rk]
  do_one_initcall+0x64/0x308
  do_init_module+0x58/0x23c
  load_module+0x1b48/0x1dc4
  init_module_from_file+0x84/0xc4
  idempotent_init_module+0x188/0x280
  __arm64_sys_finit_module+0x68/0xac
  invoke_syscall+0x48/0x110
  el0_svc_common.constprop.0+0xc8/0xe8
  do_el0_svc+0x20/0x2c
  el0_svc+0x4c/0x160
  el0t_64_sync_handler+0xa0/0xe4
  el0t_64_sync+0x198/0x19c
Code: 910003fd f9000bf3 52800013 b40000e0 (f9400013)
---[ end trace 0000000000000000 ]---

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland