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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /Documentation/parisc
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'Documentation/parisc')
-rw-r--r--Documentation/parisc/debugging.rst46
-rw-r--r--Documentation/parisc/features.rst3
-rw-r--r--Documentation/parisc/index.rst20
-rw-r--r--Documentation/parisc/registers.rst154
4 files changed, 223 insertions, 0 deletions
diff --git a/Documentation/parisc/debugging.rst b/Documentation/parisc/debugging.rst
new file mode 100644
index 000000000..de1b60402
--- /dev/null
+++ b/Documentation/parisc/debugging.rst
@@ -0,0 +1,46 @@
+=================
+PA-RISC Debugging
+=================
+
+okay, here are some hints for debugging the lower-level parts of
+linux/parisc.
+
+
+1. Absolute addresses
+=====================
+
+A lot of the assembly code currently runs in real mode, which means
+absolute addresses are used instead of virtual addresses as in the
+rest of the kernel. To translate an absolute address to a virtual
+address you can lookup in System.map, add __PAGE_OFFSET (0x10000000
+currently).
+
+
+2. HPMCs
+========
+
+When real-mode code tries to access non-existent memory, you'll get
+an HPMC instead of a kernel oops. To debug an HPMC, try to find
+the System Responder/Requestor addresses. The System Requestor
+address should match (one of the) processor HPAs (high addresses in
+the I/O range); the System Responder address is the address real-mode
+code tried to access.
+
+Typical values for the System Responder address are addresses larger
+than __PAGE_OFFSET (0x10000000) which mean a virtual address didn't
+get translated to a physical address before real-mode code tried to
+access it.
+
+
+3. Q bit fun
+============
+
+Certain, very critical code has to clear the Q bit in the PSW. What
+happens when the Q bit is cleared is the CPU does not update the
+registers interruption handlers read to find out where the machine
+was interrupted - so if you get an interruption between the instruction
+that clears the Q bit and the RFI that sets it again you don't know
+where exactly it happened. If you're lucky the IAOQ will point to the
+instruction that cleared the Q bit, if you're not it points anywhere
+at all. Usually Q bit problems will show themselves in unexplainable
+system hangs or running off the end of physical memory.
diff --git a/Documentation/parisc/features.rst b/Documentation/parisc/features.rst
new file mode 100644
index 000000000..501d7c450
--- /dev/null
+++ b/Documentation/parisc/features.rst
@@ -0,0 +1,3 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. kernel-feat:: $srctree/Documentation/features parisc
diff --git a/Documentation/parisc/index.rst b/Documentation/parisc/index.rst
new file mode 100644
index 000000000..240685751
--- /dev/null
+++ b/Documentation/parisc/index.rst
@@ -0,0 +1,20 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+====================
+PA-RISC Architecture
+====================
+
+.. toctree::
+ :maxdepth: 2
+
+ debugging
+ registers
+
+ features
+
+.. only:: subproject and html
+
+ Indices
+ =======
+
+ * :ref:`genindex`
diff --git a/Documentation/parisc/registers.rst b/Documentation/parisc/registers.rst
new file mode 100644
index 000000000..59c8ecf3e
--- /dev/null
+++ b/Documentation/parisc/registers.rst
@@ -0,0 +1,154 @@
+================================
+Register Usage for Linux/PA-RISC
+================================
+
+[ an asterisk is used for planned usage which is currently unimplemented ]
+
+General Registers as specified by ABI
+=====================================
+
+Control Registers
+-----------------
+
+=============================== ===============================================
+CR 0 (Recovery Counter) used for ptrace
+CR 1-CR 7(undefined) unused
+CR 8 (Protection ID) per-process value*
+CR 9, 12, 13 (PIDS) unused
+CR10 (CCR) lazy FPU saving*
+CR11 as specified by ABI (SAR)
+CR14 (interruption vector) initialized to fault_vector
+CR15 (EIEM) initialized to all ones*
+CR16 (Interval Timer) read for cycle count/write starts Interval Tmr
+CR17-CR22 interruption parameters
+CR19 Interrupt Instruction Register
+CR20 Interrupt Space Register
+CR21 Interrupt Offset Register
+CR22 Interrupt PSW
+CR23 (EIRR) read for pending interrupts/write clears bits
+CR24 (TR 0) Kernel Space Page Directory Pointer
+CR25 (TR 1) User Space Page Directory Pointer
+CR26 (TR 2) not used
+CR27 (TR 3) Thread descriptor pointer
+CR28 (TR 4) not used
+CR29 (TR 5) not used
+CR30 (TR 6) current / 0
+CR31 (TR 7) Temporary register, used in various places
+=============================== ===============================================
+
+Space Registers (kernel mode)
+-----------------------------
+
+=============================== ===============================================
+SR0 temporary space register
+SR4-SR7 set to 0
+SR1 temporary space register
+SR2 kernel should not clobber this
+SR3 used for userspace accesses (current process)
+=============================== ===============================================
+
+Space Registers (user mode)
+---------------------------
+
+=============================== ===============================================
+SR0 temporary space register
+SR1 temporary space register
+SR2 holds space of linux gateway page
+SR3 holds user address space value while in kernel
+SR4-SR7 Defines short address space for user/kernel
+=============================== ===============================================
+
+
+Processor Status Word
+---------------------
+
+=============================== ===============================================
+W (64-bit addresses) 0
+E (Little-endian) 0
+S (Secure Interval Timer) 0
+T (Taken Branch Trap) 0
+H (Higher-privilege trap) 0
+L (Lower-privilege trap) 0
+N (Nullify next instruction) used by C code
+X (Data memory break disable) 0
+B (Taken Branch) used by C code
+C (code address translation) 1, 0 while executing real-mode code
+V (divide step correction) used by C code
+M (HPMC mask) 0, 1 while executing HPMC handler*
+C/B (carry/borrow bits) used by C code
+O (ordered references) 1*
+F (performance monitor) 0
+R (Recovery Counter trap) 0
+Q (collect interruption state) 1 (0 in code directly preceding an rfi)
+P (Protection Identifiers) 1*
+D (Data address translation) 1, 0 while executing real-mode code
+I (external interrupt mask) used by cli()/sti() macros
+=============================== ===============================================
+
+"Invisible" Registers
+---------------------
+
+=============================== ===============================================
+PSW default W value 0
+PSW default E value 0
+Shadow Registers used by interruption handler code
+TOC enable bit 1
+=============================== ===============================================
+
+-------------------------------------------------------------------------
+
+The PA-RISC architecture defines 7 registers as "shadow registers".
+Those are used in RETURN FROM INTERRUPTION AND RESTORE instruction to reduce
+the state save and restore time by eliminating the need for general register
+(GR) saves and restores in interruption handlers.
+Shadow registers are the GRs 1, 8, 9, 16, 17, 24, and 25.
+
+-------------------------------------------------------------------------
+
+Register usage notes, originally from John Marvin, with some additional
+notes from Randolph Chung.
+
+For the general registers:
+
+r1,r2,r19-r26,r28,r29 & r31 can be used without saving them first. And of
+course, you need to save them if you care about them, before calling
+another procedure. Some of the above registers do have special meanings
+that you should be aware of:
+
+ r1:
+ The addil instruction is hardwired to place its result in r1,
+ so if you use that instruction be aware of that.
+
+ r2:
+ This is the return pointer. In general you don't want to
+ use this, since you need the pointer to get back to your
+ caller. However, it is grouped with this set of registers
+ since the caller can't rely on the value being the same
+ when you return, i.e. you can copy r2 to another register
+ and return through that register after trashing r2, and
+ that should not cause a problem for the calling routine.
+
+ r19-r22:
+ these are generally regarded as temporary registers.
+ Note that in 64 bit they are arg7-arg4.
+
+ r23-r26:
+ these are arg3-arg0, i.e. you can use them if you
+ don't care about the values that were passed in anymore.
+
+ r28,r29:
+ are ret0 and ret1. They are what you pass return values
+ in. r28 is the primary return. When returning small structures
+ r29 may also be used to pass data back to the caller.
+
+ r30:
+ stack pointer
+
+ r31:
+ the ble instruction puts the return pointer in here.
+
+
+ r3-r18,r27,r30 need to be saved and restored. r3-r18 are just
+ general purpose registers. r27 is the data pointer, and is
+ used to make references to global variables easier. r30 is
+ the stack pointer.