Re: [REGRESSION][BISECTED] stmmac: suspend hangs since 1b9707e6f1a9 ("net: stmmac: enable RPS and RBU interrupts")
From: tresonic <hidden>
Date: 2026-07-18 07:35:46
Also in:
regressions
Subsystem:
networking drivers, stmmac ethernet driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Maxime Chevallier, Linus Torvalds
Thank you for you explanations!
The interrupt is being enabled in the init_chan call in stmmac_dma_ops. Ideally, it should be disabled in a mirror function, which currently does not exist. So maybe deinit_chan() needs adding. But where to call it from? init_chan() is called from stmmac_init_dma_engine(), from stmmac_hw_setup(). stmmac_resume() does call this. So we need something in stmmac_suspend(). Maybe in stmmac_stop_all_dma()? stmmac is messy, there are often not mirror functions. If there is a stmmac_init_dma_engine() there should be stmmac_deinit_dma_engine(). If there is stmmac_hw_setup() there should be stmmac_hw_tairdown(). But none of these seem to exist. Anyway, do you want to try to implement deinit_chan() and call it from stmmac_stop_all_dma()?
Yes I'd really like to implement a solution here. This is my try, but I still have some questions: - is it ok to disable all interrupts on deinit_chan()? - maybe the interrupt could also just be disabled in stop_rx?
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
index 829a23bdad01..65c243fb829f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c@@ -125,6 +125,17 @@ static void dwmac410_dma_init_channel(struct stmmac_priv *priv, ioaddr + DMA_CHAN_INTR_ENA(dwmac4_addrs, chan)); } +static void dwmac410_dma_deinit_channel(struct stmmac_priv *priv, + void __iomem *ioaddr, u32 chan) +{ + const struct dwmac4_addrs *dwmac4_addrs = priv->plat->dwmac4_addrs; + u32 value; + + value = readl(ioaddr + DMA_CHAN_INTR_ENA(dwmac4_addrs, chan)); + value &= ~DMA_CHAN_INTR_DEFAULT_MASK_4_10; + writel(value, ioaddr + DMA_CHAN_INTR_ENA(dwmac4_addrs, chan)); +} + static void dwmac4_dma_init(void __iomem *ioaddr, struct stmmac_dma_cfg *dma_cfg) {
@@ -577,6 +588,7 @@ const struct stmmac_dma_ops dwmac410_dma_ops = { .reset = dwmac4_dma_reset, .init = dwmac4_dma_init, .init_chan = dwmac410_dma_init_channel, + .deinit_chan = dwmac410_dma_deinit_channel, .init_rx_chan = dwmac4_dma_init_rx_chan, .init_tx_chan = dwmac4_dma_init_tx_chan, .axi = dwmac4_dma_axi,
diff --git a/drivers/net/ethernet/stmicro/stmmac/hwif.h b/drivers/net/ethernet/stmicro/stmmac/hwif.h
index e6317b94fff7..04dafec021b4 100644
--- a/drivers/net/ethernet/stmicro/stmmac/hwif.h
+++ b/drivers/net/ethernet/stmicro/stmmac/hwif.h@@ -170,6 +170,8 @@ struct stmmac_dma_ops { void (*init)(void __iomem *ioaddr, struct stmmac_dma_cfg *dma_cfg); void (*init_chan)(struct stmmac_priv *priv, void __iomem *ioaddr, struct stmmac_dma_cfg *dma_cfg, u32 chan); + void (*deinit_chan)(struct stmmac_priv *priv, void __iomem *ioaddr, + u32 chan); void (*init_rx_chan)(struct stmmac_priv *priv, void __iomem *ioaddr, struct stmmac_dma_cfg *dma_cfg, dma_addr_t phy, u32 chan);
@@ -235,6 +237,8 @@ struct stmmac_dma_ops { stmmac_do_void_callback(__priv, dma, init, __args) #define stmmac_init_chan(__priv, __args...) \ stmmac_do_void_callback(__priv, dma, init_chan, __priv, __args) +#define stmmac_deinit_chan(__priv, __args...) \ + stmmac_do_void_callback(__priv, dma, deinit_chan, __priv, __args) #define stmmac_init_rx_chan(__priv, __args...) \ stmmac_do_void_callback(__priv, dma, init_rx_chan, __priv, __args) #define stmmac_init_tx_chan(__priv, __args...) \
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 2a0d7eff88d3..8504ecc3dbeb 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c@@ -2560,13 +2560,16 @@ static void stmmac_stop_all_dma(struct stmmac_priv *priv) { u8 rx_channels_count = priv->plat->rx_queues_to_use; u8 tx_channels_count = priv->plat->tx_queues_to_use; + u8 max_chan = max(rx_channels_count, tx_channels_count); u8 chan; - for (chan = 0; chan < rx_channels_count; chan++) - stmmac_stop_rx_dma(priv, chan); - - for (chan = 0; chan < tx_channels_count; chan++) - stmmac_stop_tx_dma(priv, chan); + for (chan = 0; chan < max_chan; chan++) { + if (chan < rx_channels_count) + stmmac_stop_rx_dma(priv, chan); + if (chan < tx_channels_count) + stmmac_stop_tx_dma(priv, chan); + stmmac_deinit_chan(priv, priv->ioaddr, chan); + } } /**
tresonic