kernel/linux.git/drivers/net/ethernet/stmicro, branch v7.0.12

net: stmmac: eswin: validate RGMII delay values

2026-06-01T15:54:52+00:00

[ Upstream commit c2e152f7ce3208b9333d212d41a87637ec1dd170 ] Validate rx-internal-delay-ps and tx-internal-delay-ps against the hardware capabilities of the EIC7700 MAC. The programmable RGMII delay supports 20 ps steps and a maximum value of 2540 ps. The driver previously accepted arbitrary values and silently truncated unsupported settings when converting them to hardware units. As a result, invalid device tree values could lead to unexpected delay programming and incorrect RGMII timing. Reject delay values that are not multiples of 20 ps or exceed the supported hardware range. Fixes: ea77dbbdbc4e ("net: stmmac: add Eswin EIC7700 glue driver") Signed-off-by: Zhi Li Link: https://patch.msgid.link/20260518022214.507-1-lizhi2@eswincomputing.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net: stmmac: eswin: correct RGMII delay granularity to 20 ps

2026-06-01T15:54:52+00:00

[ Upstream commit 6ffcef9bc1fc2ad8110777decd6d026e3cb468ce ] The EIC7700 MAC implements programmable RGMII delay adjustment with a granularity of 20 ps per hardware step. The driver previously converted rx-internal-delay-ps and tx-internal-delay-ps values using a 100 ps step size, resulting in incorrect delay programming. Update the conversion to use the correct 20 ps granularity so the programmed delay matches the values described in the device tree. Fixes: ea77dbbdbc4e ("net: stmmac: add Eswin EIC7700 glue driver") Signed-off-by: Zhi Li Link: https://patch.msgid.link/20260518022156.484-1-lizhi2@eswincomputing.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net: stmmac: eswin: clear TXD and RXD delay registers during initialization

2026-06-01T15:54:52+00:00

[ Upstream commit 6872fb088edc1a3c36792b301f8e4a1c35dd7c35 ] Clear the TXD and RXD delay control registers during EIC7700 DWMAC initialization. These registers may retain values programmed by the bootloader. If left unchanged, residual delays can alter the effective RGMII timing seen by the MAC and override the configuration described by the device tree. This may violate the expected RGMII timing model and can cause link instability or prevent the Ethernet controller from operating correctly. Explicitly clearing these registers ensures that the MAC delay settings are determined solely by the kernel configuration. The corresponding register offsets are optional, and the registers are only cleared when the offsets are provided in the device tree. Fixes: ea77dbbdbc4e ("net: stmmac: add Eswin EIC7700 glue driver") Signed-off-by: Zhi Li Link: https://patch.msgid.link/20260518022137.464-1-lizhi2@eswincomputing.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net: stmmac: eswin: fix HSP CSR init ordering after clock enable

2026-06-01T15:54:52+00:00

[ Upstream commit 23386defe949c0db4f746bed7098fc5e06746083 ] Fix the initialization ordering of the HSP CSR configuration in the EIC7700 DWMAC glue driver. The HSP CSR registers control MAC-side RGMII delay behavior and must only be accessed after the corresponding clocks are enabled. The previous implementation could trigger register access before clock enablement, leading to undefined behavior depending on boot state. Move the HSP CSR configuration into the post-clock-enable initialization path to ensure all register accesses occur under valid clock domains. This change ensures deterministic initialization and prevents clock-dependent register access failures during probe or resume. Fixes: ea77dbbdbc4e ("net: stmmac: add Eswin EIC7700 glue driver") Signed-off-by: Zhi Li Link: https://patch.msgid.link/20260518022055.444-1-lizhi2@eswincomputing.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net: stmmac: Prevent NULL deref when RX memory exhausted

2026-05-14T13:31:20+00:00

[ Upstream commit 0bb05e6adfa99a2ea1fee1125cc0953409f83ed8 ] The CPU receives frames from the MAC through conventional DMA: the CPU allocates buffers for the MAC, then the MAC fills them and returns ownership to the CPU. For each hardware RX queue, the CPU and MAC coordinate through a shared ring array of DMA descriptors: one descriptor per DMA buffer. Each descriptor includes the buffer's physical address and a status flag ("OWN") indicating which side owns the buffer: OWN=0 for CPU, OWN=1 for MAC. The CPU is only allowed to set the flag and the MAC is only allowed to clear it, and both must move through the ring in sequence: thus the ring is used for both "submissions" and "completions." In the stmmac driver, stmmac_rx() bookmarks its position in the ring with the `cur_rx` index. The main receive loop in that function checks for rx_descs[cur_rx].own=0, gives the corresponding buffer to the network stack (NULLing the pointer), and increments `cur_rx` modulo the ring size. After the loop exits, stmmac_rx_refill(), which bookmarks its position with `dirty_rx`, allocates fresh buffers and rearms the descriptors (setting OWN=1). If it fails any allocation, it simply stops early (leaving OWN=0) and will retry where it left off when next called. This means descriptors have a three-stage lifecycle (terms my own): - `empty` (OWN=1, buffer valid) - `full` (OWN=0, buffer valid and populated) - `dirty` (OWN=0, buffer NULL) But because stmmac_rx() only checks OWN, it confuses `full`/`dirty`. In the past (see 'Fixes:'), there was a bug where the loop could cycle `cur_rx` all the way back to the first descriptor it dirtied, resulting in a NULL dereference when mistaken for `full`. The aforementioned commit resolved that *specific* failure by capping the loop's iteration limit at `dma_rx_size - 1`, but this is only a partial fix: if the previous stmmac_rx_refill() didn't complete, then there are leftover `dirty` descriptors that the loop might encounter without needing to cycle fully around. The current code therefore panics (see 'Closes:') when stmmac_rx_refill() is memory-starved long enough for `cur_rx` to catch up to `dirty_rx`. Fix this by explicitly checking, before advancing `cur_rx`, if the next entry is dirty; exit the loop if so. This prevents processing of the final, used descriptor until stmmac_rx_refill() succeeds, but fully prevents the `cur_rx == dirty_rx` ambiguity as the previous bugfix intended: so remove the clamp as well. Since stmmac_rx_zc() is a copy-paste-and-tweak of stmmac_rx() and the code structure is identical, any fix to stmmac_rx() will also need a corresponding fix for stmmac_rx_zc(). Therefore, apply the same check there. In stmmac_rx() (not stmmac_rx_zc()), a related bug remains: after the MAC sets OWN=0 on the final descriptor, it will be unable to send any further DMA-complete IRQs until it's given more `empty` descriptors. Currently, the driver simply *hopes* that the next stmmac_rx_refill() succeeds, risking an indefinite stall of the receive process if not. But this is not a regression, so it can be addressed in a future change. Fixes: b6cb4541853c7 ("net: stmmac: avoid rx queue overrun") Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221010 Cc: stable@vger.kernel.org Suggested-by: Russell King Signed-off-by: Sam Edwards Link: https://patch.msgid.link/20260422044503.5349-1-CFSworks@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

net: stmmac: rename STMMAC_GET_ENTRY() -> STMMAC_NEXT_ENTRY()

2026-05-14T13:31:20+00:00

[ Upstream commit 6b4286e0550814cdc4b897f881ec1fa8b0313227 ] STMMAC_GET_ENTRY() doesn't describe what this macro is doing - it is incrementing the provided index for the circular array of descriptors. Replace "GET" with "NEXT" as this better describes the action here. Signed-off-by: Russell King (Oracle) Link: https://patch.msgid.link/E1w2vba-0000000DbWo-1oL5@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski Stable-dep-of: 0bb05e6adfa9 ("net: stmmac: Prevent NULL deref when RX memory exhausted") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

net: stmmac: dwmac-motorcomm: fix eFUSE MAC address read failure

2026-04-08T01:21:00+00:00

This patch fixes an issue where reading the MAC address from the eFUSE fails due to a race condition. The root cause was identified by comparing the driver's behavior with a custom U-Boot port. In U-Boot, the MAC address was read successfully every time because the driver was loaded later in the boot process, giving the hardware ample time to initialize. In Linux, reading the eFUSE immediately returns all zeros, resulting in a fallback to a random MAC address. Hardware cold-boot testing revealed that the eFUSE controller requires a short settling time to load its internal data. Adding a 2000-5000us delay after the reset ensures the hardware is fully ready, allowing the native MAC address to be read consistently. Fixes: 02ff155ea281 ("net: stmmac: Add glue driver for Motorcomm YT6801 ethernet controller") Reported-by: Georg Gottleuber Closes: https://lore.kernel.org/24cfefff-1233-4745-8c47-812b502d5d19@tuxedocomputers.com Signed-off-by: Johan Alvarado Reviewed-by: Yao Zi Reviewed-by: Andrew Lunn Link: https://patch.msgid.link/fc5992a4-9532-49c3-8ec1-c2f8c5b84ca1@smtp-relay.sendinblue.com Signed-off-by: Jakub Kicinski

net: stmmac: Fix PTP ref clock for Tegra234

2026-04-03T23:02:21+00:00

Since commit 030ce919e114 ("net: stmmac: make sure that ptp_rate is not 0 before configuring timestamping") was added the following error is observed on Tegra234: ERR KERN tegra-mgbe 6800000.ethernet eth0: Invalid PTP clock rate WARNING KERN tegra-mgbe 6800000.ethernet eth0: PTP init failed It turns out that the Tegra234 device-tree binding defines the PTP ref clock name as 'ptp-ref' and not 'ptp_ref' and the above commit now exposes this and that the PTP clock is not configured correctly. In order to update device-tree to use the correct 'ptp_ref' name, update the Tegra MGBE driver to use 'ptp_ref' by default and fallback to using 'ptp-ref' if this clock name is present. Fixes: d8ca113724e7 ("net: stmmac: tegra: Add MGBE support") Signed-off-by: Jon Hunter Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260401102941.17466-2-jonathanh@nvidia.com Signed-off-by: Jakub Kicinski

net: stmmac: fix integer underflow in chain mode

2026-04-03T01:28:10+00:00

The jumbo_frm() chain-mode implementation unconditionally computes len = nopaged_len - bmax; where nopaged_len = skb_headlen(skb) (linear bytes only) and bmax is BUF_SIZE_8KiB or BUF_SIZE_2KiB. However, the caller stmmac_xmit() decides to invoke jumbo_frm() based on skb->len (total length including page fragments): is_jumbo = stmmac_is_jumbo_frm(priv, skb->len, enh_desc); When a packet has a small linear portion (nopaged_len <= bmax) but a large total length due to page fragments (skb->len > bmax), the subtraction wraps as an unsigned integer, producing a huge len value (~0xFFFFxxxx). This causes the while (len != 0) loop to execute hundreds of thousands of iterations, passing skb->data + bmax * i pointers far beyond the skb buffer to dma_map_single(). On IOMMU-less SoCs (the typical deployment for stmmac), this maps arbitrary kernel memory to the DMA engine, constituting a kernel memory disclosure and potential memory corruption from hardware. Fix this by introducing a buf_len local variable clamped to min(nopaged_len, bmax). Computing len = nopaged_len - buf_len is then always safe: it is zero when the linear portion fits within a single descriptor, causing the while (len != 0) loop to be skipped naturally, and the fragment loop in stmmac_xmit() handles page fragments afterward. Fixes: 286a83721720 ("stmmac: add CHAINED descriptor mode support (V4)") Cc: stable@vger.kernel.org Signed-off-by: Tyllis Xu Link: https://patch.msgid.link/20260401044708.1386919-1-LivelyCarpet87@gmail.com Signed-off-by: Jakub Kicinski

net: stmmac: skip VLAN restore when VLAN hash ops are missing

2026-04-01T02:45:26+00:00

stmmac_vlan_restore() unconditionally calls stmmac_vlan_update() when NETIF_F_VLAN_FEATURES is set. On platforms where priv->hw->vlan (or ->update_vlan_hash) is not provided, stmmac_update_vlan_hash() returns -EINVAL via stmmac_do_void_callback(), resulting in a spurious "Failed to restore VLANs" error even when no VLAN filtering is in use. Remove not needed comment. Remove not used return value from stmmac_vlan_restore(). Tested on Orange Pi Zero 3. Fixes: bd7ad51253a7 ("net: stmmac: Fix VLAN HW state restore") Signed-off-by: Michal Piekos Link: https://patch.msgid.link/20260328-vlan-restore-error-v4-1-f88624c530dc@mmpsystems.pl Signed-off-by: Jakub Kicinski