linux_dsm_epyc7002/include/linux/dsa/sja1105.h

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/* SPDX-License-Identifier: GPL-2.0
* Copyright (c) 2019, Vladimir Oltean <olteanv@gmail.com>
*/
/* Included by drivers/net/dsa/sja1105/sja1105.h and net/dsa/tag_sja1105.c */
#ifndef _NET_DSA_SJA1105_H
#define _NET_DSA_SJA1105_H
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
#include <linux/dsa/8021q.h>
#include <net/dsa.h>
#define ETH_P_SJA1105 ETH_P_DSA_8021Q
#define ETH_P_SJA1105_META 0x0008
/* IEEE 802.3 Annex 57A: Slow Protocols PDUs (01:80:C2:xx:xx:xx) */
#define SJA1105_LINKLOCAL_FILTER_A 0x0180C2000000ull
#define SJA1105_LINKLOCAL_FILTER_A_MASK 0xFFFFFF000000ull
/* IEEE 1588 Annex F: Transport of PTP over Ethernet (01:1B:19:xx:xx:xx) */
#define SJA1105_LINKLOCAL_FILTER_B 0x011B19000000ull
#define SJA1105_LINKLOCAL_FILTER_B_MASK 0xFFFFFF000000ull
/* Source and Destination MAC of follow-up meta frames.
* Whereas the choice of SMAC only affects the unique identification of the
* switch as sender of meta frames, the DMAC must be an address that is present
* in the DSA master port's multicast MAC filter.
* 01-80-C2-00-00-0E is a good choice for this, as all profiles of IEEE 1588
* over L2 use this address for some purpose already.
*/
#define SJA1105_META_SMAC 0x222222222222ull
#define SJA1105_META_DMAC 0x0180C200000Eull
net: dsa: sja1105: Fix sleeping while atomic in .port_hwtstamp_set Currently this stack trace can be seen with CONFIG_DEBUG_ATOMIC_SLEEP=y: [ 41.568348] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909 [ 41.576757] in_atomic(): 1, irqs_disabled(): 0, pid: 208, name: ptp4l [ 41.583212] INFO: lockdep is turned off. [ 41.587123] CPU: 1 PID: 208 Comm: ptp4l Not tainted 5.3.0-rc6-01445-ge950f2d4bc7f-dirty #1827 [ 41.599873] [<c0313d7c>] (unwind_backtrace) from [<c030e13c>] (show_stack+0x10/0x14) [ 41.607584] [<c030e13c>] (show_stack) from [<c1212d50>] (dump_stack+0xd4/0x100) [ 41.614863] [<c1212d50>] (dump_stack) from [<c037dfc8>] (___might_sleep+0x1c8/0x2b4) [ 41.622574] [<c037dfc8>] (___might_sleep) from [<c122ea90>] (__mutex_lock+0x48/0xab8) [ 41.630368] [<c122ea90>] (__mutex_lock) from [<c122f51c>] (mutex_lock_nested+0x1c/0x24) [ 41.638340] [<c122f51c>] (mutex_lock_nested) from [<c0c6fe08>] (sja1105_static_config_reload+0x30/0x27c) [ 41.647779] [<c0c6fe08>] (sja1105_static_config_reload) from [<c0c7015c>] (sja1105_hwtstamp_set+0x108/0x1cc) [ 41.657562] [<c0c7015c>] (sja1105_hwtstamp_set) from [<c0feb650>] (dev_ifsioc+0x18c/0x330) [ 41.665788] [<c0feb650>] (dev_ifsioc) from [<c0febbd8>] (dev_ioctl+0x320/0x6e8) [ 41.673064] [<c0febbd8>] (dev_ioctl) from [<c0f8b1f4>] (sock_ioctl+0x334/0x5e8) [ 41.680340] [<c0f8b1f4>] (sock_ioctl) from [<c05404a8>] (do_vfs_ioctl+0xb0/0xa10) [ 41.687789] [<c05404a8>] (do_vfs_ioctl) from [<c0540e3c>] (ksys_ioctl+0x34/0x58) [ 41.695151] [<c0540e3c>] (ksys_ioctl) from [<c0301000>] (ret_fast_syscall+0x0/0x28) [ 41.702768] Exception stack(0xe8495fa8 to 0xe8495ff0) [ 41.707796] 5fa0: beff4a8c 00000001 00000011 000089b0 beff4a8c beff4a80 [ 41.715933] 5fc0: beff4a8c 00000001 0000000c 00000036 b6fa98c8 004e19c1 00000001 00000000 [ 41.724069] 5fe0: 004dcedc beff4a6c 004c0738 b6e7af4c [ 41.729860] BUG: scheduling while atomic: ptp4l/208/0x00000002 [ 41.735682] INFO: lockdep is turned off. Enabling RX timestamping will logically disturb the fastpath (processing of meta frames). Replace bool hwts_rx_en with a bit that is checked atomically from the fastpath and temporarily unset from the sleepable context during a change of the RX timestamping process (a destructive operation anyways, requires switch reset). If found unset, the fastpath (net/dsa/tag_sja1105.c) will just drop any received meta frame and not take the meta_lock at all. Fixes: a602afd200f5 ("net: dsa: sja1105: Expose PTP timestamping ioctls to userspace") Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-02 01:58:19 +07:00
#define SJA1105_HWTS_RX_EN 0
/* Global tagger data: each struct sja1105_port has a reference to
* the structure defined in struct sja1105_private.
*/
struct sja1105_tagger_data {
struct sk_buff *stampable_skb;
/* Protects concurrent access to the meta state machine
* from taggers running on multiple ports on SMP systems
*/
spinlock_t meta_lock;
net: dsa: sja1105: Fix sleeping while atomic in .port_hwtstamp_set Currently this stack trace can be seen with CONFIG_DEBUG_ATOMIC_SLEEP=y: [ 41.568348] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909 [ 41.576757] in_atomic(): 1, irqs_disabled(): 0, pid: 208, name: ptp4l [ 41.583212] INFO: lockdep is turned off. [ 41.587123] CPU: 1 PID: 208 Comm: ptp4l Not tainted 5.3.0-rc6-01445-ge950f2d4bc7f-dirty #1827 [ 41.599873] [<c0313d7c>] (unwind_backtrace) from [<c030e13c>] (show_stack+0x10/0x14) [ 41.607584] [<c030e13c>] (show_stack) from [<c1212d50>] (dump_stack+0xd4/0x100) [ 41.614863] [<c1212d50>] (dump_stack) from [<c037dfc8>] (___might_sleep+0x1c8/0x2b4) [ 41.622574] [<c037dfc8>] (___might_sleep) from [<c122ea90>] (__mutex_lock+0x48/0xab8) [ 41.630368] [<c122ea90>] (__mutex_lock) from [<c122f51c>] (mutex_lock_nested+0x1c/0x24) [ 41.638340] [<c122f51c>] (mutex_lock_nested) from [<c0c6fe08>] (sja1105_static_config_reload+0x30/0x27c) [ 41.647779] [<c0c6fe08>] (sja1105_static_config_reload) from [<c0c7015c>] (sja1105_hwtstamp_set+0x108/0x1cc) [ 41.657562] [<c0c7015c>] (sja1105_hwtstamp_set) from [<c0feb650>] (dev_ifsioc+0x18c/0x330) [ 41.665788] [<c0feb650>] (dev_ifsioc) from [<c0febbd8>] (dev_ioctl+0x320/0x6e8) [ 41.673064] [<c0febbd8>] (dev_ioctl) from [<c0f8b1f4>] (sock_ioctl+0x334/0x5e8) [ 41.680340] [<c0f8b1f4>] (sock_ioctl) from [<c05404a8>] (do_vfs_ioctl+0xb0/0xa10) [ 41.687789] [<c05404a8>] (do_vfs_ioctl) from [<c0540e3c>] (ksys_ioctl+0x34/0x58) [ 41.695151] [<c0540e3c>] (ksys_ioctl) from [<c0301000>] (ret_fast_syscall+0x0/0x28) [ 41.702768] Exception stack(0xe8495fa8 to 0xe8495ff0) [ 41.707796] 5fa0: beff4a8c 00000001 00000011 000089b0 beff4a8c beff4a80 [ 41.715933] 5fc0: beff4a8c 00000001 0000000c 00000036 b6fa98c8 004e19c1 00000001 00000000 [ 41.724069] 5fe0: 004dcedc beff4a6c 004c0738 b6e7af4c [ 41.729860] BUG: scheduling while atomic: ptp4l/208/0x00000002 [ 41.735682] INFO: lockdep is turned off. Enabling RX timestamping will logically disturb the fastpath (processing of meta frames). Replace bool hwts_rx_en with a bit that is checked atomically from the fastpath and temporarily unset from the sleepable context during a change of the RX timestamping process (a destructive operation anyways, requires switch reset). If found unset, the fastpath (net/dsa/tag_sja1105.c) will just drop any received meta frame and not take the meta_lock at all. Fixes: a602afd200f5 ("net: dsa: sja1105: Expose PTP timestamping ioctls to userspace") Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-02 01:58:19 +07:00
unsigned long state;
};
struct sja1105_skb_cb {
u32 meta_tstamp;
};
#define SJA1105_SKB_CB(skb) \
((struct sja1105_skb_cb *)DSA_SKB_CB_PRIV(skb))
struct sja1105_port {
u16 subvlan_map[DSA_8021Q_N_SUBVLAN];
net: dsa: Make deferred_xmit private to sja1105 There are 3 things that are wrong with the DSA deferred xmit mechanism: 1. Its introduction has made the DSA hotpath ever so slightly more inefficient for everybody, since DSA_SKB_CB(skb)->deferred_xmit needs to be initialized to false for every transmitted frame, in order to figure out whether the driver requested deferral or not (a very rare occasion, rare even for the only driver that does use this mechanism: sja1105). That was necessary to avoid kfree_skb from freeing the skb. 2. Because L2 PTP is a link-local protocol like STP, it requires management routes and deferred xmit with this switch. But as opposed to STP, the deferred work mechanism needs to schedule the packet rather quickly for the TX timstamp to be collected in time and sent to user space. But there is no provision for controlling the scheduling priority of this deferred xmit workqueue. Too bad this is a rather specific requirement for a feature that nobody else uses (more below). 3. Perhaps most importantly, it makes the DSA core adhere a bit too much to the NXP company-wide policy "Innovate Where It Doesn't Matter". The sja1105 is probably the only DSA switch that requires some frames sent from the CPU to be routed to the slave port via an out-of-band configuration (register write) rather than in-band (DSA tag). And there are indeed very good reasons to not want to do that: if that out-of-band register is at the other end of a slow bus such as SPI, then you limit that Ethernet flow's throughput to effectively the throughput of the SPI bus. So hardware vendors should definitely not be encouraged to design this way. We do _not_ want more widespread use of this mechanism. Luckily we have a solution for each of the 3 issues: For 1, we can just remove that variable in the skb->cb and counteract the effect of kfree_skb with skb_get, much to the same effect. The advantage, of course, being that anybody who doesn't use deferred xmit doesn't need to do any extra operation in the hotpath. For 2, we can create a kernel thread for each port's deferred xmit work. If the user switch ports are named swp0, swp1, swp2, the kernel threads will be named swp0_xmit, swp1_xmit, swp2_xmit (there appears to be a 15 character length limit on kernel thread names). With this, the user can change the scheduling priority with chrt $(pidof swp2_xmit). For 3, we can actually move the entire implementation to the sja1105 driver. So this patch deletes the generic implementation from the DSA core and adds a new one, more adequate to the requirements of PTP TX timestamping, in sja1105_main.c. Suggested-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-04 07:37:10 +07:00
struct kthread_worker *xmit_worker;
struct kthread_work xmit_work;
struct sk_buff_head xmit_queue;
struct sja1105_tagger_data *data;
struct dsa_port *dp;
bool hwts_tx_en;
net: dsa: sja1105: prepare tagger for handling DSA tags and VLAN simultaneously In VLAN-unaware mode, sja1105 uses VLAN tags with a custom TPID of 0xdadb. While in the yet-to-be introduced best_effort_vlan_filtering mode, it needs to work with normal VLAN TPID values. A complication arises when we must transmit a VLAN-tagged packet to the switch when it's in VLAN-aware mode. We need to construct a packet with 2 VLAN tags, and the switch will use the outer header for routing and pop it on egress. But sadly, here the 2 hardware generations don't behave the same: - E/T switches won't pop an ETH_P_8021AD tag on egress, it seems (packets will remain double-tagged). - P/Q/R/S switches will drop a packet with 2 ETH_P_8021Q tags (it looks like it tries to prevent VLAN hopping). But looks like the reverse is also true: - E/T switches have no problem popping the outer tag from packets with 2 ETH_P_8021Q tags. - P/Q/R/S will have no problem popping a single tag even if that is ETH_P_8021AD. So it is clear that if we want the hardware to work with dsa_8021q tagging in VLAN-aware mode, we need to send different TPIDs depending on revision. Keep that information in priv->info->qinq_tpid. The per-port tagger structure will hold an xmit_tpid value that depends not only upon the qinq_tpid, but also upon the VLAN awareness state itself (in case we must transmit using 0xdadb). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-13 00:20:32 +07:00
u16 xmit_tpid;
};
#endif /* _NET_DSA_SJA1105_H */