aboutsummaryrefslogtreecommitdiff
path: root/drivers/tty/serial/liteuart.c
diff options
context:
space:
mode:
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 /drivers/tty/serial/liteuart.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
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 '')
-rw-r--r--drivers/tty/serial/liteuart.c438
1 files changed, 438 insertions, 0 deletions
diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c
new file mode 100644
index 000000000..062812fe1
--- /dev/null
+++ b/drivers/tty/serial/liteuart.c
@@ -0,0 +1,438 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * LiteUART serial controller (LiteX) Driver
+ *
+ * Copyright (C) 2019-2020 Antmicro <www.antmicro.com>
+ */
+
+#include <linux/console.h>
+#include <linux/litex.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+#include <linux/slab.h>
+#include <linux/timer.h>
+#include <linux/tty_flip.h>
+#include <linux/xarray.h>
+
+/*
+ * CSRs definitions (base address offsets + width)
+ *
+ * The definitions below are true for LiteX SoC configured for 8-bit CSR Bus,
+ * 32-bit aligned.
+ *
+ * Supporting other configurations might require new definitions or a more
+ * generic way of indexing the LiteX CSRs.
+ *
+ * For more details on how CSRs are defined and handled in LiteX, see comments
+ * in the LiteX SoC Driver: drivers/soc/litex/litex_soc_ctrl.c
+ */
+#define OFF_RXTX 0x00
+#define OFF_TXFULL 0x04
+#define OFF_RXEMPTY 0x08
+#define OFF_EV_STATUS 0x0c
+#define OFF_EV_PENDING 0x10
+#define OFF_EV_ENABLE 0x14
+
+/* events */
+#define EV_TX 0x1
+#define EV_RX 0x2
+
+struct liteuart_port {
+ struct uart_port port;
+ struct timer_list timer;
+ u32 id;
+};
+
+#define to_liteuart_port(port) container_of(port, struct liteuart_port, port)
+
+static DEFINE_XARRAY_FLAGS(liteuart_array, XA_FLAGS_ALLOC);
+
+#ifdef CONFIG_SERIAL_LITEUART_CONSOLE
+static struct console liteuart_console;
+#endif
+
+static struct uart_driver liteuart_driver = {
+ .owner = THIS_MODULE,
+ .driver_name = "liteuart",
+ .dev_name = "ttyLXU",
+ .major = 0,
+ .minor = 0,
+ .nr = CONFIG_SERIAL_LITEUART_MAX_PORTS,
+#ifdef CONFIG_SERIAL_LITEUART_CONSOLE
+ .cons = &liteuart_console,
+#endif
+};
+
+static void liteuart_timer(struct timer_list *t)
+{
+ struct liteuart_port *uart = from_timer(uart, t, timer);
+ struct uart_port *port = &uart->port;
+ unsigned char __iomem *membase = port->membase;
+ unsigned int flg = TTY_NORMAL;
+ int ch;
+ unsigned long status;
+
+ while ((status = !litex_read8(membase + OFF_RXEMPTY)) == 1) {
+ ch = litex_read8(membase + OFF_RXTX);
+ port->icount.rx++;
+
+ /* necessary for RXEMPTY to refresh its value */
+ litex_write8(membase + OFF_EV_PENDING, EV_TX | EV_RX);
+
+ /* no overflow bits in status */
+ if (!(uart_handle_sysrq_char(port, ch)))
+ uart_insert_char(port, status, 0, ch, flg);
+
+ tty_flip_buffer_push(&port->state->port);
+ }
+
+ mod_timer(&uart->timer, jiffies + uart_poll_timeout(port));
+}
+
+static void liteuart_putchar(struct uart_port *port, unsigned char ch)
+{
+ while (litex_read8(port->membase + OFF_TXFULL))
+ cpu_relax();
+
+ litex_write8(port->membase + OFF_RXTX, ch);
+}
+
+static unsigned int liteuart_tx_empty(struct uart_port *port)
+{
+ /* not really tx empty, just checking if tx is not full */
+ if (!litex_read8(port->membase + OFF_TXFULL))
+ return TIOCSER_TEMT;
+
+ return 0;
+}
+
+static void liteuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ /* modem control register is not present in LiteUART */
+}
+
+static unsigned int liteuart_get_mctrl(struct uart_port *port)
+{
+ return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
+}
+
+static void liteuart_stop_tx(struct uart_port *port)
+{
+}
+
+static void liteuart_start_tx(struct uart_port *port)
+{
+ struct circ_buf *xmit = &port->state->xmit;
+ unsigned char ch;
+
+ if (unlikely(port->x_char)) {
+ litex_write8(port->membase + OFF_RXTX, port->x_char);
+ port->icount.tx++;
+ port->x_char = 0;
+ } else if (!uart_circ_empty(xmit)) {
+ while (xmit->head != xmit->tail) {
+ ch = xmit->buf[xmit->tail];
+ uart_xmit_advance(port, 1);
+ liteuart_putchar(port, ch);
+ }
+ }
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+}
+
+static void liteuart_stop_rx(struct uart_port *port)
+{
+ struct liteuart_port *uart = to_liteuart_port(port);
+
+ /* just delete timer */
+ del_timer(&uart->timer);
+}
+
+static void liteuart_break_ctl(struct uart_port *port, int break_state)
+{
+ /* LiteUART doesn't support sending break signal */
+}
+
+static int liteuart_startup(struct uart_port *port)
+{
+ struct liteuart_port *uart = to_liteuart_port(port);
+
+ /* disable events */
+ litex_write8(port->membase + OFF_EV_ENABLE, 0);
+
+ /* prepare timer for polling */
+ timer_setup(&uart->timer, liteuart_timer, 0);
+ mod_timer(&uart->timer, jiffies + uart_poll_timeout(port));
+
+ return 0;
+}
+
+static void liteuart_shutdown(struct uart_port *port)
+{
+}
+
+static void liteuart_set_termios(struct uart_port *port, struct ktermios *new,
+ const struct ktermios *old)
+{
+ unsigned int baud;
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /* update baudrate */
+ baud = uart_get_baud_rate(port, new, old, 0, 460800);
+ uart_update_timeout(port, new->c_cflag, baud);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *liteuart_type(struct uart_port *port)
+{
+ return "liteuart";
+}
+
+static void liteuart_release_port(struct uart_port *port)
+{
+}
+
+static int liteuart_request_port(struct uart_port *port)
+{
+ return 0;
+}
+
+static void liteuart_config_port(struct uart_port *port, int flags)
+{
+ /*
+ * Driver core for serial ports forces a non-zero value for port type.
+ * Write an arbitrary value here to accommodate the serial core driver,
+ * as ID part of UAPI is redundant.
+ */
+ port->type = 1;
+}
+
+static int liteuart_verify_port(struct uart_port *port,
+ struct serial_struct *ser)
+{
+ if (port->type != PORT_UNKNOWN && ser->type != 1)
+ return -EINVAL;
+
+ return 0;
+}
+
+static const struct uart_ops liteuart_ops = {
+ .tx_empty = liteuart_tx_empty,
+ .set_mctrl = liteuart_set_mctrl,
+ .get_mctrl = liteuart_get_mctrl,
+ .stop_tx = liteuart_stop_tx,
+ .start_tx = liteuart_start_tx,
+ .stop_rx = liteuart_stop_rx,
+ .break_ctl = liteuart_break_ctl,
+ .startup = liteuart_startup,
+ .shutdown = liteuart_shutdown,
+ .set_termios = liteuart_set_termios,
+ .type = liteuart_type,
+ .release_port = liteuart_release_port,
+ .request_port = liteuart_request_port,
+ .config_port = liteuart_config_port,
+ .verify_port = liteuart_verify_port,
+};
+
+static int liteuart_probe(struct platform_device *pdev)
+{
+ struct liteuart_port *uart;
+ struct uart_port *port;
+ struct xa_limit limit;
+ int dev_id, ret;
+
+ /* look for aliases; auto-enumerate for free index if not found */
+ dev_id = of_alias_get_id(pdev->dev.of_node, "serial");
+ if (dev_id < 0)
+ limit = XA_LIMIT(0, CONFIG_SERIAL_LITEUART_MAX_PORTS);
+ else
+ limit = XA_LIMIT(dev_id, dev_id);
+
+ uart = devm_kzalloc(&pdev->dev, sizeof(struct liteuart_port), GFP_KERNEL);
+ if (!uart)
+ return -ENOMEM;
+
+ ret = xa_alloc(&liteuart_array, &dev_id, uart, limit, GFP_KERNEL);
+ if (ret)
+ return ret;
+
+ uart->id = dev_id;
+ port = &uart->port;
+
+ /* get membase */
+ port->membase = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
+ if (IS_ERR(port->membase)) {
+ ret = PTR_ERR(port->membase);
+ goto err_erase_id;
+ }
+
+ /* values not from device tree */
+ port->dev = &pdev->dev;
+ port->iotype = UPIO_MEM;
+ port->flags = UPF_BOOT_AUTOCONF;
+ port->ops = &liteuart_ops;
+ port->regshift = 2;
+ port->fifosize = 16;
+ port->iobase = 1;
+ port->type = PORT_UNKNOWN;
+ port->line = dev_id;
+ spin_lock_init(&port->lock);
+
+ platform_set_drvdata(pdev, port);
+
+ ret = uart_add_one_port(&liteuart_driver, &uart->port);
+ if (ret)
+ goto err_erase_id;
+
+ return 0;
+
+err_erase_id:
+ xa_erase(&liteuart_array, uart->id);
+
+ return ret;
+}
+
+static int liteuart_remove(struct platform_device *pdev)
+{
+ struct uart_port *port = platform_get_drvdata(pdev);
+ struct liteuart_port *uart = to_liteuart_port(port);
+
+ uart_remove_one_port(&liteuart_driver, port);
+ xa_erase(&liteuart_array, uart->id);
+
+ return 0;
+}
+
+static const struct of_device_id liteuart_of_match[] = {
+ { .compatible = "litex,liteuart" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, liteuart_of_match);
+
+static struct platform_driver liteuart_platform_driver = {
+ .probe = liteuart_probe,
+ .remove = liteuart_remove,
+ .driver = {
+ .name = "liteuart",
+ .of_match_table = liteuart_of_match,
+ },
+};
+
+#ifdef CONFIG_SERIAL_LITEUART_CONSOLE
+
+static void liteuart_console_write(struct console *co, const char *s,
+ unsigned int count)
+{
+ struct liteuart_port *uart;
+ struct uart_port *port;
+ unsigned long flags;
+
+ uart = (struct liteuart_port *)xa_load(&liteuart_array, co->index);
+ port = &uart->port;
+
+ spin_lock_irqsave(&port->lock, flags);
+ uart_console_write(port, s, count, liteuart_putchar);
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static int liteuart_console_setup(struct console *co, char *options)
+{
+ struct liteuart_port *uart;
+ struct uart_port *port;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ uart = (struct liteuart_port *)xa_load(&liteuart_array, co->index);
+ if (!uart)
+ return -ENODEV;
+
+ port = &uart->port;
+ if (!port->membase)
+ return -ENODEV;
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+ return uart_set_options(port, co, baud, parity, bits, flow);
+}
+
+static struct console liteuart_console = {
+ .name = "liteuart",
+ .write = liteuart_console_write,
+ .device = uart_console_device,
+ .setup = liteuart_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &liteuart_driver,
+};
+
+static int __init liteuart_console_init(void)
+{
+ register_console(&liteuart_console);
+
+ return 0;
+}
+console_initcall(liteuart_console_init);
+
+static void early_liteuart_write(struct console *console, const char *s,
+ unsigned int count)
+{
+ struct earlycon_device *device = console->data;
+ struct uart_port *port = &device->port;
+
+ uart_console_write(port, s, count, liteuart_putchar);
+}
+
+static int __init early_liteuart_setup(struct earlycon_device *device,
+ const char *options)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->con->write = early_liteuart_write;
+ return 0;
+}
+
+OF_EARLYCON_DECLARE(liteuart, "litex,liteuart", early_liteuart_setup);
+#endif /* CONFIG_SERIAL_LITEUART_CONSOLE */
+
+static int __init liteuart_init(void)
+{
+ int res;
+
+ res = uart_register_driver(&liteuart_driver);
+ if (res)
+ return res;
+
+ res = platform_driver_register(&liteuart_platform_driver);
+ if (res) {
+ uart_unregister_driver(&liteuart_driver);
+ return res;
+ }
+
+ return 0;
+}
+
+static void __exit liteuart_exit(void)
+{
+ platform_driver_unregister(&liteuart_platform_driver);
+ uart_unregister_driver(&liteuart_driver);
+}
+
+module_init(liteuart_init);
+module_exit(liteuart_exit);
+
+MODULE_AUTHOR("Antmicro <www.antmicro.com>");
+MODULE_DESCRIPTION("LiteUART serial driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:liteuart");