[PATCH net-next] net: stmmac: dwmac-renesas-gbeth: Add PM suspend/resume callbacks

[Russell King (Oracle)]

On Sat, Jul 05, 2025 at 06:03:24PM +0100, Biju Das wrote:
> Add PM suspend/resume callbacks for RZ/G3E SMARC EVK.
> 
> The PM deep entry is executed by pressing the SLEEP button and exit from
> entry is by pressing the power button.
> 
> Logs:
> root at smarc-rzg3e:~# PM: suspend entry (deep)
> Filesystems sync: 0.115 seconds
> Freezing user space processes
> Freezing user space processes completed (elapsed 0.002 seconds)
> OOM killer disabled.
> Freezing remaining freezable tasks
> Freezing remaining freezable tasks completed (elapsed 0.001 seconds)
> printk: Suspending console(s) (use no_console_suspend to debug)
> NOTICE:  BL2: v2.10.5(release):2.10.5/rz_soc_dev-162-g7148ba838
> NOTICE:  BL2: Built : 14:23:58, Jul  5 2025
> NOTICE:  BL2: SYS_LSI_MODE: 0x13e06
> NOTICE:  BL2: SYS_LSI_DEVID: 0x8679447
> NOTICE:  BL2: SYS_LSI_PRR: 0x0
> NOTICE:  BL2: Booting BL31
> renesas-gbeth 15c30000.ethernet end0: Link is Down
> Disabling non-boot CPUs ...
> psci: CPU3 killed (polled 0 ms)
> psci: CPU2 killed (polled 0 ms)
> psci: CPU1 killed (polled 0 ms)
> Enabling non-boot CPUs ...
> Detected VIPT I-cache on CPU1
> GICv3: CPU1: found redistributor 100 region 0:0x0000000014960000
> CPU1: Booted secondary processor 0x0000000100 [0x412fd050]
> CPU1 is up
> Detected VIPT I-cache on CPU2
> GICv3: CPU2: found redistributor 200 region 0:0x0000000014980000
> CPU2: Booted secondary processor 0x0000000200 [0x412fd050]
> CPU2 is up
> Detected VIPT I-cache on CPU3
> GICv3: CPU3: found redistributor 300 region 0:0x00000000149a0000
> CPU3: Booted secondary processor 0x0000000300 [0x412fd050]
> CPU3 is up
> dwmac4: Master AXI performs fixed burst length
> 15c30000.ethernet end0: No Safety Features support found
> 15c30000.ethernet end0: IEEE 1588-2008 Advanced Timestamp supported
> 15c30000.ethernet end0: configuring for phy/rgmii-id link mode
> dwmac4: Master AXI performs fixed burst length
> 15c40000.ethernet end1: No Safety Features support found
> 15c40000.ethernet end1: IEEE 1588-2008 Advanced Timestamp supported
> 15c40000.ethernet end1: configuring for phy/rgmii-id link mode
> OOM killer enabled.
> Restarting tasks: Starting
> Restarting tasks: Done
> random: crng reseeded on system resumption
> PM: suspend exit
> 
> 15c30000.ethernet end0: Link is Up - 1Gbps/Full - flow control rx/tx
> root at smarc-rzg3e:~# ifconfig end0 192.168.10.7 up
> root at smarc-rzg3e:~# ping 192.168.10.1
> PING 192.168.10.1 (192.168.10.1) 56(84) bytes of data.
> 64 bytes from 192.168.10.1: icmp_seq=1 ttl=64 time=2.05 ms
> 64 bytes from 192.168.10.1: icmp_seq=2 ttl=64 time=0.928 ms

You should also test with the interface configured before suspend/resume
and confirm that it continues working afterwards without being
reconfigured.

> Signed-off-by: Biju Das <biju.das.jz at bp.renesas.com>

Reviewed-by: Russell King (Oracle) <rmk+kernel at armlinux.org.uk>

Thanks!

-- 
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