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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 /drivers/i2c/busses/i2c-octeon-core.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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 'drivers/i2c/busses/i2c-octeon-core.c')
-rw-r--r--drivers/i2c/busses/i2c-octeon-core.c792
1 files changed, 792 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c
new file mode 100644
index 000000000..845eda70b
--- /dev/null
+++ b/drivers/i2c/busses/i2c-octeon-core.c
@@ -0,0 +1,792 @@
+/*
+ * (C) Copyright 2009-2010
+ * Nokia Siemens Networks, michael.lawnick.ext@nsn.com
+ *
+ * Portions Copyright (C) 2010 - 2016 Cavium, Inc.
+ *
+ * This file contains the shared part of the driver for the i2c adapter in
+ * Cavium Networks' OCTEON processors and ThunderX SOCs.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include "i2c-octeon-core.h"
+
+/* interrupt service routine */
+irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
+{
+ struct octeon_i2c *i2c = dev_id;
+
+ i2c->int_disable(i2c);
+ wake_up(&i2c->queue);
+
+ return IRQ_HANDLED;
+}
+
+static bool octeon_i2c_test_iflg(struct octeon_i2c *i2c)
+{
+ return (octeon_i2c_ctl_read(i2c) & TWSI_CTL_IFLG);
+}
+
+/**
+ * octeon_i2c_wait - wait for the IFLG to be set
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_wait(struct octeon_i2c *i2c)
+{
+ long time_left;
+
+ /*
+ * Some chip revisions don't assert the irq in the interrupt
+ * controller. So we must poll for the IFLG change.
+ */
+ if (i2c->broken_irq_mode) {
+ u64 end = get_jiffies_64() + i2c->adap.timeout;
+
+ while (!octeon_i2c_test_iflg(i2c) &&
+ time_before64(get_jiffies_64(), end))
+ usleep_range(I2C_OCTEON_EVENT_WAIT / 2, I2C_OCTEON_EVENT_WAIT);
+
+ return octeon_i2c_test_iflg(i2c) ? 0 : -ETIMEDOUT;
+ }
+
+ i2c->int_enable(i2c);
+ time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_iflg(i2c),
+ i2c->adap.timeout);
+ i2c->int_disable(i2c);
+
+ if (i2c->broken_irq_check && !time_left &&
+ octeon_i2c_test_iflg(i2c)) {
+ dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
+ i2c->broken_irq_mode = true;
+ return 0;
+ }
+
+ if (!time_left)
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+static bool octeon_i2c_hlc_test_valid(struct octeon_i2c *i2c)
+{
+ return (__raw_readq(i2c->twsi_base + SW_TWSI(i2c)) & SW_TWSI_V) == 0;
+}
+
+static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c)
+{
+ /* clear ST/TS events, listen for neither */
+ octeon_i2c_write_int(i2c, TWSI_INT_ST_INT | TWSI_INT_TS_INT);
+}
+
+/*
+ * Cleanup low-level state & enable high-level controller.
+ */
+static void octeon_i2c_hlc_enable(struct octeon_i2c *i2c)
+{
+ int try = 0;
+ u64 val;
+
+ if (i2c->hlc_enabled)
+ return;
+ i2c->hlc_enabled = true;
+
+ while (1) {
+ val = octeon_i2c_ctl_read(i2c);
+ if (!(val & (TWSI_CTL_STA | TWSI_CTL_STP)))
+ break;
+
+ /* clear IFLG event */
+ if (val & TWSI_CTL_IFLG)
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+
+ if (try++ > 100) {
+ pr_err("%s: giving up\n", __func__);
+ break;
+ }
+
+ /* spin until any start/stop has finished */
+ udelay(10);
+ }
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_CE | TWSI_CTL_AAK | TWSI_CTL_ENAB);
+}
+
+static void octeon_i2c_hlc_disable(struct octeon_i2c *i2c)
+{
+ if (!i2c->hlc_enabled)
+ return;
+
+ i2c->hlc_enabled = false;
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+}
+
+/**
+ * octeon_i2c_hlc_wait - wait for an HLC operation to complete
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns 0 on success, otherwise -ETIMEDOUT.
+ */
+static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
+{
+ int time_left;
+
+ /*
+ * Some cn38xx boards don't assert the irq in the interrupt
+ * controller. So we must poll for the valid bit change.
+ */
+ if (i2c->broken_irq_mode) {
+ u64 end = get_jiffies_64() + i2c->adap.timeout;
+
+ while (!octeon_i2c_hlc_test_valid(i2c) &&
+ time_before64(get_jiffies_64(), end))
+ usleep_range(I2C_OCTEON_EVENT_WAIT / 2, I2C_OCTEON_EVENT_WAIT);
+
+ return octeon_i2c_hlc_test_valid(i2c) ? 0 : -ETIMEDOUT;
+ }
+
+ i2c->hlc_int_enable(i2c);
+ time_left = wait_event_timeout(i2c->queue,
+ octeon_i2c_hlc_test_valid(i2c),
+ i2c->adap.timeout);
+ i2c->hlc_int_disable(i2c);
+ if (!time_left)
+ octeon_i2c_hlc_int_clear(i2c);
+
+ if (i2c->broken_irq_check && !time_left &&
+ octeon_i2c_hlc_test_valid(i2c)) {
+ dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
+ i2c->broken_irq_mode = true;
+ return 0;
+ }
+
+ if (!time_left)
+ return -ETIMEDOUT;
+ return 0;
+}
+
+static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
+{
+ u8 stat;
+
+ /*
+ * This is ugly... in HLC mode the status is not in the status register
+ * but in the lower 8 bits of SW_TWSI.
+ */
+ if (i2c->hlc_enabled)
+ stat = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
+ else
+ stat = octeon_i2c_stat_read(i2c);
+
+ switch (stat) {
+ /* Everything is fine */
+ case STAT_IDLE:
+ case STAT_AD2W_ACK:
+ case STAT_RXADDR_ACK:
+ case STAT_TXADDR_ACK:
+ case STAT_TXDATA_ACK:
+ return 0;
+
+ /* ACK allowed on pre-terminal bytes only */
+ case STAT_RXDATA_ACK:
+ if (!final_read)
+ return 0;
+ return -EIO;
+
+ /* NAK allowed on terminal byte only */
+ case STAT_RXDATA_NAK:
+ if (final_read)
+ return 0;
+ return -EIO;
+
+ /* Arbitration lost */
+ case STAT_LOST_ARB_38:
+ case STAT_LOST_ARB_68:
+ case STAT_LOST_ARB_78:
+ case STAT_LOST_ARB_B0:
+ return -EAGAIN;
+
+ /* Being addressed as slave, should back off & listen */
+ case STAT_SLAVE_60:
+ case STAT_SLAVE_70:
+ case STAT_GENDATA_ACK:
+ case STAT_GENDATA_NAK:
+ return -EOPNOTSUPP;
+
+ /* Core busy as slave */
+ case STAT_SLAVE_80:
+ case STAT_SLAVE_88:
+ case STAT_SLAVE_A0:
+ case STAT_SLAVE_A8:
+ case STAT_SLAVE_LOST:
+ case STAT_SLAVE_NAK:
+ case STAT_SLAVE_ACK:
+ return -EOPNOTSUPP;
+
+ case STAT_TXDATA_NAK:
+ case STAT_BUS_ERROR:
+ return -EIO;
+ case STAT_TXADDR_NAK:
+ case STAT_RXADDR_NAK:
+ case STAT_AD2W_NAK:
+ return -ENXIO;
+ default:
+ dev_err(i2c->dev, "unhandled state: %d\n", stat);
+ return -EIO;
+ }
+}
+
+static int octeon_i2c_recovery(struct octeon_i2c *i2c)
+{
+ int ret;
+
+ ret = i2c_recover_bus(&i2c->adap);
+ if (ret)
+ /* recover failed, try hardware re-init */
+ ret = octeon_i2c_init_lowlevel(i2c);
+ return ret;
+}
+
+/**
+ * octeon_i2c_start - send START to the bus
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_start(struct octeon_i2c *i2c)
+{
+ int ret;
+ u8 stat;
+
+ octeon_i2c_hlc_disable(i2c);
+
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STA);
+ ret = octeon_i2c_wait(i2c);
+ if (ret)
+ goto error;
+
+ stat = octeon_i2c_stat_read(i2c);
+ if (stat == STAT_START || stat == STAT_REP_START)
+ /* START successful, bail out */
+ return 0;
+
+error:
+ /* START failed, try to recover */
+ ret = octeon_i2c_recovery(i2c);
+ return (ret) ? ret : -EAGAIN;
+}
+
+/* send STOP to the bus */
+static void octeon_i2c_stop(struct octeon_i2c *i2c)
+{
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STP);
+}
+
+/**
+ * octeon_i2c_read - receive data from the bus via low-level controller
+ * @i2c: The struct octeon_i2c
+ * @target: Target address
+ * @data: Pointer to the location to store the data
+ * @rlength: Length of the data
+ * @recv_len: flag for length byte
+ *
+ * The address is sent over the bus, then the data is read.
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
+ u8 *data, u16 *rlength, bool recv_len)
+{
+ int i, result, length = *rlength;
+ bool final_read = false;
+
+ octeon_i2c_data_write(i2c, (target << 1) | 1);
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+
+ result = octeon_i2c_wait(i2c);
+ if (result)
+ return result;
+
+ /* address OK ? */
+ result = octeon_i2c_check_status(i2c, false);
+ if (result)
+ return result;
+
+ for (i = 0; i < length; i++) {
+ /*
+ * For the last byte to receive TWSI_CTL_AAK must not be set.
+ *
+ * A special case is I2C_M_RECV_LEN where we don't know the
+ * additional length yet. If recv_len is set we assume we're
+ * not reading the final byte and therefore need to set
+ * TWSI_CTL_AAK.
+ */
+ if ((i + 1 == length) && !(recv_len && i == 0))
+ final_read = true;
+
+ /* clear iflg to allow next event */
+ if (final_read)
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+ else
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_AAK);
+
+ result = octeon_i2c_wait(i2c);
+ if (result)
+ return result;
+
+ data[i] = octeon_i2c_data_read(i2c, &result);
+ if (result)
+ return result;
+ if (recv_len && i == 0) {
+ if (data[i] > I2C_SMBUS_BLOCK_MAX)
+ return -EPROTO;
+ length += data[i];
+ }
+
+ result = octeon_i2c_check_status(i2c, final_read);
+ if (result)
+ return result;
+ }
+ *rlength = length;
+ return 0;
+}
+
+/**
+ * octeon_i2c_write - send data to the bus via low-level controller
+ * @i2c: The struct octeon_i2c
+ * @target: Target address
+ * @data: Pointer to the data to be sent
+ * @length: Length of the data
+ *
+ * The address is sent over the bus, then the data.
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
+ const u8 *data, int length)
+{
+ int i, result;
+
+ octeon_i2c_data_write(i2c, target << 1);
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+
+ result = octeon_i2c_wait(i2c);
+ if (result)
+ return result;
+
+ for (i = 0; i < length; i++) {
+ result = octeon_i2c_check_status(i2c, false);
+ if (result)
+ return result;
+
+ octeon_i2c_data_write(i2c, data[i]);
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+
+ result = octeon_i2c_wait(i2c);
+ if (result)
+ return result;
+ }
+
+ return 0;
+}
+
+/* high-level-controller pure read of up to 8 bytes */
+static int octeon_i2c_hlc_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ int i, j, ret = 0;
+ u64 cmd;
+
+ octeon_i2c_hlc_enable(i2c);
+ octeon_i2c_hlc_int_clear(i2c);
+
+ cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64)(msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10;
+ else
+ cmd |= SW_TWSI_OP_7;
+
+ octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI(i2c));
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
+ if ((cmd & SW_TWSI_R) == 0)
+ return octeon_i2c_check_status(i2c, false);
+
+ for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
+ msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
+
+ if (msgs[0].len > 4) {
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT(i2c));
+ for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
+ msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
+ }
+
+err:
+ return ret;
+}
+
+/* high-level-controller pure write of up to 8 bytes */
+static int octeon_i2c_hlc_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ int i, j, ret = 0;
+ u64 cmd;
+
+ octeon_i2c_hlc_enable(i2c);
+ octeon_i2c_hlc_int_clear(i2c);
+
+ cmd = SW_TWSI_V | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64)(msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10;
+ else
+ cmd |= SW_TWSI_OP_7;
+
+ for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
+ cmd |= (u64)msgs[0].buf[j] << (8 * i);
+
+ if (msgs[0].len > 4) {
+ u64 ext = 0;
+
+ for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
+ ext |= (u64)msgs[0].buf[j] << (8 * i);
+ octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT(i2c));
+ }
+
+ octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI(i2c));
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
+ if ((cmd & SW_TWSI_R) == 0)
+ return octeon_i2c_check_status(i2c, false);
+
+err:
+ return ret;
+}
+
+/* high-level-controller composite write+read, msg0=addr, msg1=data */
+static int octeon_i2c_hlc_comp_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ int i, j, ret = 0;
+ u64 cmd;
+
+ octeon_i2c_hlc_enable(i2c);
+
+ cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10_IA;
+ else
+ cmd |= SW_TWSI_OP_7_IA;
+
+ if (msgs[0].len == 2) {
+ u64 ext = 0;
+
+ cmd |= SW_TWSI_EIA;
+ ext = (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+ cmd |= (u64)msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
+ octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT(i2c));
+ } else {
+ cmd |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+ }
+
+ octeon_i2c_hlc_int_clear(i2c);
+ octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI(i2c));
+
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
+ if ((cmd & SW_TWSI_R) == 0)
+ return octeon_i2c_check_status(i2c, false);
+
+ for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
+ msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
+
+ if (msgs[1].len > 4) {
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT(i2c));
+ for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
+ msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
+ }
+
+err:
+ return ret;
+}
+
+/* high-level-controller composite write+write, m[0]len<=2, m[1]len<=8 */
+static int octeon_i2c_hlc_comp_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ bool set_ext = false;
+ int i, j, ret = 0;
+ u64 cmd, ext = 0;
+
+ octeon_i2c_hlc_enable(i2c);
+
+ cmd = SW_TWSI_V | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10_IA;
+ else
+ cmd |= SW_TWSI_OP_7_IA;
+
+ if (msgs[0].len == 2) {
+ cmd |= SW_TWSI_EIA;
+ ext |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+ set_ext = true;
+ cmd |= (u64)msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
+ } else {
+ cmd |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+ }
+
+ for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
+ cmd |= (u64)msgs[1].buf[j] << (8 * i);
+
+ if (msgs[1].len > 4) {
+ for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
+ ext |= (u64)msgs[1].buf[j] << (8 * i);
+ set_ext = true;
+ }
+ if (set_ext)
+ octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT(i2c));
+
+ octeon_i2c_hlc_int_clear(i2c);
+ octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI(i2c));
+
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
+ if ((cmd & SW_TWSI_R) == 0)
+ return octeon_i2c_check_status(i2c, false);
+
+err:
+ return ret;
+}
+
+/**
+ * octeon_i2c_xfer - The driver's master_xfer function
+ * @adap: Pointer to the i2c_adapter structure
+ * @msgs: Pointer to the messages to be processed
+ * @num: Length of the MSGS array
+ *
+ * Returns the number of messages processed, or a negative errno on failure.
+ */
+int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+ struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+ int i, ret = 0;
+
+ if (num == 1) {
+ if (msgs[0].len > 0 && msgs[0].len <= 8) {
+ if (msgs[0].flags & I2C_M_RD)
+ ret = octeon_i2c_hlc_read(i2c, msgs);
+ else
+ ret = octeon_i2c_hlc_write(i2c, msgs);
+ goto out;
+ }
+ } else if (num == 2) {
+ if ((msgs[0].flags & I2C_M_RD) == 0 &&
+ (msgs[1].flags & I2C_M_RECV_LEN) == 0 &&
+ msgs[0].len > 0 && msgs[0].len <= 2 &&
+ msgs[1].len > 0 && msgs[1].len <= 8 &&
+ msgs[0].addr == msgs[1].addr) {
+ if (msgs[1].flags & I2C_M_RD)
+ ret = octeon_i2c_hlc_comp_read(i2c, msgs);
+ else
+ ret = octeon_i2c_hlc_comp_write(i2c, msgs);
+ goto out;
+ }
+ }
+
+ for (i = 0; ret == 0 && i < num; i++) {
+ struct i2c_msg *pmsg = &msgs[i];
+
+ /* zero-length messages are not supported */
+ if (!pmsg->len) {
+ ret = -EOPNOTSUPP;
+ break;
+ }
+
+ ret = octeon_i2c_start(i2c);
+ if (ret)
+ return ret;
+
+ if (pmsg->flags & I2C_M_RD)
+ ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf,
+ &pmsg->len, pmsg->flags & I2C_M_RECV_LEN);
+ else
+ ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
+ pmsg->len);
+ }
+ octeon_i2c_stop(i2c);
+out:
+ return (ret != 0) ? ret : num;
+}
+
+/* calculate and set clock divisors */
+void octeon_i2c_set_clock(struct octeon_i2c *i2c)
+{
+ int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
+ int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
+
+ for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
+ /*
+ * An mdiv value of less than 2 seems to not work well
+ * with ds1337 RTCs, so we constrain it to larger values.
+ */
+ for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
+ /*
+ * For given ndiv and mdiv values check the
+ * two closest thp values.
+ */
+ tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
+ tclk *= (1 << ndiv_idx);
+ thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
+
+ for (inc = 0; inc <= 1; inc++) {
+ thp_idx = thp_base + inc;
+ if (thp_idx < 5 || thp_idx > 0xff)
+ continue;
+
+ foscl = i2c->sys_freq / (2 * (thp_idx + 1));
+ foscl = foscl / (1 << ndiv_idx);
+ foscl = foscl / (mdiv_idx + 1) / 10;
+ diff = abs(foscl - i2c->twsi_freq);
+ if (diff < delta_hz) {
+ delta_hz = diff;
+ thp = thp_idx;
+ mdiv = mdiv_idx;
+ ndiv = ndiv_idx;
+ }
+ }
+ }
+ }
+ octeon_i2c_reg_write(i2c, SW_TWSI_OP_TWSI_CLK, thp);
+ octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
+}
+
+int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c)
+{
+ u8 status = 0;
+ int tries;
+
+ /* reset controller */
+ octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_RST, 0);
+
+ for (tries = 10; tries && status != STAT_IDLE; tries--) {
+ udelay(1);
+ status = octeon_i2c_stat_read(i2c);
+ if (status == STAT_IDLE)
+ break;
+ }
+
+ if (status != STAT_IDLE) {
+ dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n",
+ __func__, status);
+ return -EIO;
+ }
+
+ /* toggle twice to force both teardowns */
+ octeon_i2c_hlc_enable(i2c);
+ octeon_i2c_hlc_disable(i2c);
+ return 0;
+}
+
+static int octeon_i2c_get_scl(struct i2c_adapter *adap)
+{
+ struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+ u64 state;
+
+ state = octeon_i2c_read_int(i2c);
+ return state & TWSI_INT_SCL;
+}
+
+static void octeon_i2c_set_scl(struct i2c_adapter *adap, int val)
+{
+ struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+
+ octeon_i2c_write_int(i2c, val ? 0 : TWSI_INT_SCL_OVR);
+}
+
+static int octeon_i2c_get_sda(struct i2c_adapter *adap)
+{
+ struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+ u64 state;
+
+ state = octeon_i2c_read_int(i2c);
+ return state & TWSI_INT_SDA;
+}
+
+static void octeon_i2c_prepare_recovery(struct i2c_adapter *adap)
+{
+ struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+
+ octeon_i2c_hlc_disable(i2c);
+ octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_RST, 0);
+ /* wait for software reset to settle */
+ udelay(5);
+
+ /*
+ * Bring control register to a good state regardless
+ * of HLC state.
+ */
+ octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+
+ octeon_i2c_write_int(i2c, 0);
+}
+
+static void octeon_i2c_unprepare_recovery(struct i2c_adapter *adap)
+{
+ struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+
+ /*
+ * Generate STOP to finish the unfinished transaction.
+ * Can't generate STOP via the TWSI CTL register
+ * since it could bring the TWSI controller into an inoperable state.
+ */
+ octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR | TWSI_INT_SCL_OVR);
+ udelay(5);
+ octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR);
+ udelay(5);
+ octeon_i2c_write_int(i2c, 0);
+}
+
+struct i2c_bus_recovery_info octeon_i2c_recovery_info = {
+ .recover_bus = i2c_generic_scl_recovery,
+ .get_scl = octeon_i2c_get_scl,
+ .set_scl = octeon_i2c_set_scl,
+ .get_sda = octeon_i2c_get_sda,
+ .prepare_recovery = octeon_i2c_prepare_recovery,
+ .unprepare_recovery = octeon_i2c_unprepare_recovery,
+};