From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- drivers/spi/spi-cadence.c | 754 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 754 insertions(+) create mode 100644 drivers/spi/spi-cadence.c (limited to 'drivers/spi/spi-cadence.c') diff --git a/drivers/spi/spi-cadence.c b/drivers/spi/spi-cadence.c new file mode 100644 index 000000000..6a7f7df1e --- /dev/null +++ b/drivers/spi/spi-cadence.c @@ -0,0 +1,754 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Cadence SPI controller driver (master mode only) + * + * Copyright (C) 2008 - 2014 Xilinx, Inc. + * + * based on Blackfin On-Chip SPI Driver (spi_bfin5xx.c) + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Name of this driver */ +#define CDNS_SPI_NAME "cdns-spi" + +/* Register offset definitions */ +#define CDNS_SPI_CR 0x00 /* Configuration Register, RW */ +#define CDNS_SPI_ISR 0x04 /* Interrupt Status Register, RO */ +#define CDNS_SPI_IER 0x08 /* Interrupt Enable Register, WO */ +#define CDNS_SPI_IDR 0x0c /* Interrupt Disable Register, WO */ +#define CDNS_SPI_IMR 0x10 /* Interrupt Enabled Mask Register, RO */ +#define CDNS_SPI_ER 0x14 /* Enable/Disable Register, RW */ +#define CDNS_SPI_DR 0x18 /* Delay Register, RW */ +#define CDNS_SPI_TXD 0x1C /* Data Transmit Register, WO */ +#define CDNS_SPI_RXD 0x20 /* Data Receive Register, RO */ +#define CDNS_SPI_SICR 0x24 /* Slave Idle Count Register, RW */ +#define CDNS_SPI_THLD 0x28 /* Transmit FIFO Watermark Register,RW */ + +#define SPI_AUTOSUSPEND_TIMEOUT 3000 +/* + * SPI Configuration Register bit Masks + * + * This register contains various control bits that affect the operation + * of the SPI controller + */ +#define CDNS_SPI_CR_MANSTRT 0x00010000 /* Manual TX Start */ +#define CDNS_SPI_CR_CPHA 0x00000004 /* Clock Phase Control */ +#define CDNS_SPI_CR_CPOL 0x00000002 /* Clock Polarity Control */ +#define CDNS_SPI_CR_SSCTRL 0x00003C00 /* Slave Select Mask */ +#define CDNS_SPI_CR_PERI_SEL 0x00000200 /* Peripheral Select Decode */ +#define CDNS_SPI_CR_BAUD_DIV 0x00000038 /* Baud Rate Divisor Mask */ +#define CDNS_SPI_CR_MSTREN 0x00000001 /* Master Enable Mask */ +#define CDNS_SPI_CR_MANSTRTEN 0x00008000 /* Manual TX Enable Mask */ +#define CDNS_SPI_CR_SSFORCE 0x00004000 /* Manual SS Enable Mask */ +#define CDNS_SPI_CR_BAUD_DIV_4 0x00000008 /* Default Baud Div Mask */ +#define CDNS_SPI_CR_DEFAULT (CDNS_SPI_CR_MSTREN | \ + CDNS_SPI_CR_SSCTRL | \ + CDNS_SPI_CR_SSFORCE | \ + CDNS_SPI_CR_BAUD_DIV_4) + +/* + * SPI Configuration Register - Baud rate and slave select + * + * These are the values used in the calculation of baud rate divisor and + * setting the slave select. + */ + +#define CDNS_SPI_BAUD_DIV_MAX 7 /* Baud rate divisor maximum */ +#define CDNS_SPI_BAUD_DIV_MIN 1 /* Baud rate divisor minimum */ +#define CDNS_SPI_BAUD_DIV_SHIFT 3 /* Baud rate divisor shift in CR */ +#define CDNS_SPI_SS_SHIFT 10 /* Slave Select field shift in CR */ +#define CDNS_SPI_SS0 0x1 /* Slave Select zero */ +#define CDNS_SPI_NOSS 0xF /* No Slave select */ + +/* + * SPI Interrupt Registers bit Masks + * + * All the four interrupt registers (Status/Mask/Enable/Disable) have the same + * bit definitions. + */ +#define CDNS_SPI_IXR_TXOW 0x00000004 /* SPI TX FIFO Overwater */ +#define CDNS_SPI_IXR_MODF 0x00000002 /* SPI Mode Fault */ +#define CDNS_SPI_IXR_RXNEMTY 0x00000010 /* SPI RX FIFO Not Empty */ +#define CDNS_SPI_IXR_DEFAULT (CDNS_SPI_IXR_TXOW | \ + CDNS_SPI_IXR_MODF) +#define CDNS_SPI_IXR_TXFULL 0x00000008 /* SPI TX Full */ +#define CDNS_SPI_IXR_ALL 0x0000007F /* SPI all interrupts */ + +/* + * SPI Enable Register bit Masks + * + * This register is used to enable or disable the SPI controller + */ +#define CDNS_SPI_ER_ENABLE 0x00000001 /* SPI Enable Bit Mask */ +#define CDNS_SPI_ER_DISABLE 0x0 /* SPI Disable Bit Mask */ + +/* Default number of chip select lines */ +#define CDNS_SPI_DEFAULT_NUM_CS 4 + +/** + * struct cdns_spi - This definition defines spi driver instance + * @regs: Virtual address of the SPI controller registers + * @ref_clk: Pointer to the peripheral clock + * @pclk: Pointer to the APB clock + * @speed_hz: Current SPI bus clock speed in Hz + * @txbuf: Pointer to the TX buffer + * @rxbuf: Pointer to the RX buffer + * @tx_bytes: Number of bytes left to transfer + * @rx_bytes: Number of bytes requested + * @dev_busy: Device busy flag + * @is_decoded_cs: Flag for decoder property set or not + * @tx_fifo_depth: Depth of the TX FIFO + */ +struct cdns_spi { + void __iomem *regs; + struct clk *ref_clk; + struct clk *pclk; + unsigned int clk_rate; + u32 speed_hz; + const u8 *txbuf; + u8 *rxbuf; + int tx_bytes; + int rx_bytes; + u8 dev_busy; + u32 is_decoded_cs; + unsigned int tx_fifo_depth; +}; + +/* Macros for the SPI controller read/write */ +static inline u32 cdns_spi_read(struct cdns_spi *xspi, u32 offset) +{ + return readl_relaxed(xspi->regs + offset); +} + +static inline void cdns_spi_write(struct cdns_spi *xspi, u32 offset, u32 val) +{ + writel_relaxed(val, xspi->regs + offset); +} + +/** + * cdns_spi_init_hw - Initialize the hardware and configure the SPI controller + * @xspi: Pointer to the cdns_spi structure + * + * On reset the SPI controller is configured to be in master mode, baud rate + * divisor is set to 4, threshold value for TX FIFO not full interrupt is set + * to 1 and size of the word to be transferred as 8 bit. + * This function initializes the SPI controller to disable and clear all the + * interrupts, enable manual slave select and manual start, deselect all the + * chip select lines, and enable the SPI controller. + */ +static void cdns_spi_init_hw(struct cdns_spi *xspi) +{ + u32 ctrl_reg = CDNS_SPI_CR_DEFAULT; + + if (xspi->is_decoded_cs) + ctrl_reg |= CDNS_SPI_CR_PERI_SEL; + + cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_DISABLE); + cdns_spi_write(xspi, CDNS_SPI_IDR, CDNS_SPI_IXR_ALL); + + /* Clear the RX FIFO */ + while (cdns_spi_read(xspi, CDNS_SPI_ISR) & CDNS_SPI_IXR_RXNEMTY) + cdns_spi_read(xspi, CDNS_SPI_RXD); + + cdns_spi_write(xspi, CDNS_SPI_ISR, CDNS_SPI_IXR_ALL); + cdns_spi_write(xspi, CDNS_SPI_CR, ctrl_reg); + cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_ENABLE); +} + +/** + * cdns_spi_chipselect - Select or deselect the chip select line + * @spi: Pointer to the spi_device structure + * @is_high: Select(0) or deselect (1) the chip select line + */ +static void cdns_spi_chipselect(struct spi_device *spi, bool is_high) +{ + struct cdns_spi *xspi = spi_master_get_devdata(spi->master); + u32 ctrl_reg; + + ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR); + + if (is_high) { + /* Deselect the slave */ + ctrl_reg |= CDNS_SPI_CR_SSCTRL; + } else { + /* Select the slave */ + ctrl_reg &= ~CDNS_SPI_CR_SSCTRL; + if (!(xspi->is_decoded_cs)) + ctrl_reg |= ((~(CDNS_SPI_SS0 << spi->chip_select)) << + CDNS_SPI_SS_SHIFT) & + CDNS_SPI_CR_SSCTRL; + else + ctrl_reg |= (spi->chip_select << CDNS_SPI_SS_SHIFT) & + CDNS_SPI_CR_SSCTRL; + } + + cdns_spi_write(xspi, CDNS_SPI_CR, ctrl_reg); +} + +/** + * cdns_spi_config_clock_mode - Sets clock polarity and phase + * @spi: Pointer to the spi_device structure + * + * Sets the requested clock polarity and phase. + */ +static void cdns_spi_config_clock_mode(struct spi_device *spi) +{ + struct cdns_spi *xspi = spi_master_get_devdata(spi->master); + u32 ctrl_reg, new_ctrl_reg; + + new_ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR); + ctrl_reg = new_ctrl_reg; + + /* Set the SPI clock phase and clock polarity */ + new_ctrl_reg &= ~(CDNS_SPI_CR_CPHA | CDNS_SPI_CR_CPOL); + if (spi->mode & SPI_CPHA) + new_ctrl_reg |= CDNS_SPI_CR_CPHA; + if (spi->mode & SPI_CPOL) + new_ctrl_reg |= CDNS_SPI_CR_CPOL; + + if (new_ctrl_reg != ctrl_reg) { + /* + * Just writing the CR register does not seem to apply the clock + * setting changes. This is problematic when changing the clock + * polarity as it will cause the SPI slave to see spurious clock + * transitions. To workaround the issue toggle the ER register. + */ + cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_DISABLE); + cdns_spi_write(xspi, CDNS_SPI_CR, new_ctrl_reg); + cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_ENABLE); + } +} + +/** + * cdns_spi_config_clock_freq - Sets clock frequency + * @spi: Pointer to the spi_device structure + * @transfer: Pointer to the spi_transfer structure which provides + * information about next transfer setup parameters + * + * Sets the requested clock frequency. + * Note: If the requested frequency is not an exact match with what can be + * obtained using the prescalar value the driver sets the clock frequency which + * is lower than the requested frequency (maximum lower) for the transfer. If + * the requested frequency is higher or lower than that is supported by the SPI + * controller the driver will set the highest or lowest frequency supported by + * controller. + */ +static void cdns_spi_config_clock_freq(struct spi_device *spi, + struct spi_transfer *transfer) +{ + struct cdns_spi *xspi = spi_master_get_devdata(spi->master); + u32 ctrl_reg, baud_rate_val; + unsigned long frequency; + + frequency = xspi->clk_rate; + + ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR); + + /* Set the clock frequency */ + if (xspi->speed_hz != transfer->speed_hz) { + /* first valid value is 1 */ + baud_rate_val = CDNS_SPI_BAUD_DIV_MIN; + while ((baud_rate_val < CDNS_SPI_BAUD_DIV_MAX) && + (frequency / (2 << baud_rate_val)) > transfer->speed_hz) + baud_rate_val++; + + ctrl_reg &= ~CDNS_SPI_CR_BAUD_DIV; + ctrl_reg |= baud_rate_val << CDNS_SPI_BAUD_DIV_SHIFT; + + xspi->speed_hz = frequency / (2 << baud_rate_val); + } + cdns_spi_write(xspi, CDNS_SPI_CR, ctrl_reg); +} + +/** + * cdns_spi_setup_transfer - Configure SPI controller for specified transfer + * @spi: Pointer to the spi_device structure + * @transfer: Pointer to the spi_transfer structure which provides + * information about next transfer setup parameters + * + * Sets the operational mode of SPI controller for the next SPI transfer and + * sets the requested clock frequency. + * + * Return: Always 0 + */ +static int cdns_spi_setup_transfer(struct spi_device *spi, + struct spi_transfer *transfer) +{ + struct cdns_spi *xspi = spi_master_get_devdata(spi->master); + + cdns_spi_config_clock_freq(spi, transfer); + + dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u clock speed\n", + __func__, spi->mode, spi->bits_per_word, + xspi->speed_hz); + + return 0; +} + +/** + * cdns_spi_fill_tx_fifo - Fills the TX FIFO with as many bytes as possible + * @xspi: Pointer to the cdns_spi structure + */ +static void cdns_spi_fill_tx_fifo(struct cdns_spi *xspi) +{ + unsigned long trans_cnt = 0; + + while ((trans_cnt < xspi->tx_fifo_depth) && + (xspi->tx_bytes > 0)) { + + /* When xspi in busy condition, bytes may send failed, + * then spi control did't work thoroughly, add one byte delay + */ + if (cdns_spi_read(xspi, CDNS_SPI_ISR) & + CDNS_SPI_IXR_TXFULL) + udelay(10); + + if (xspi->txbuf) + cdns_spi_write(xspi, CDNS_SPI_TXD, *xspi->txbuf++); + else + cdns_spi_write(xspi, CDNS_SPI_TXD, 0); + + xspi->tx_bytes--; + trans_cnt++; + } +} + +/** + * cdns_spi_irq - Interrupt service routine of the SPI controller + * @irq: IRQ number + * @dev_id: Pointer to the xspi structure + * + * This function handles TX empty and Mode Fault interrupts only. + * On TX empty interrupt this function reads the received data from RX FIFO and + * fills the TX FIFO if there is any data remaining to be transferred. + * On Mode Fault interrupt this function indicates that transfer is completed, + * the SPI subsystem will identify the error as the remaining bytes to be + * transferred is non-zero. + * + * Return: IRQ_HANDLED when handled; IRQ_NONE otherwise. + */ +static irqreturn_t cdns_spi_irq(int irq, void *dev_id) +{ + struct spi_master *master = dev_id; + struct cdns_spi *xspi = spi_master_get_devdata(master); + irqreturn_t status; + u32 intr_status; + + status = IRQ_NONE; + intr_status = cdns_spi_read(xspi, CDNS_SPI_ISR); + cdns_spi_write(xspi, CDNS_SPI_ISR, intr_status); + + if (intr_status & CDNS_SPI_IXR_MODF) { + /* Indicate that transfer is completed, the SPI subsystem will + * identify the error as the remaining bytes to be + * transferred is non-zero + */ + cdns_spi_write(xspi, CDNS_SPI_IDR, CDNS_SPI_IXR_DEFAULT); + spi_finalize_current_transfer(master); + status = IRQ_HANDLED; + } else if (intr_status & CDNS_SPI_IXR_TXOW) { + unsigned long trans_cnt; + + trans_cnt = xspi->rx_bytes - xspi->tx_bytes; + + /* Read out the data from the RX FIFO */ + while (trans_cnt) { + u8 data; + + data = cdns_spi_read(xspi, CDNS_SPI_RXD); + if (xspi->rxbuf) + *xspi->rxbuf++ = data; + + xspi->rx_bytes--; + trans_cnt--; + } + + if (xspi->tx_bytes) { + /* There is more data to send */ + cdns_spi_fill_tx_fifo(xspi); + } else { + /* Transfer is completed */ + cdns_spi_write(xspi, CDNS_SPI_IDR, + CDNS_SPI_IXR_DEFAULT); + spi_finalize_current_transfer(master); + } + status = IRQ_HANDLED; + } + + return status; +} + +static int cdns_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + cdns_spi_config_clock_mode(msg->spi); + return 0; +} + +/** + * cdns_transfer_one - Initiates the SPI transfer + * @master: Pointer to spi_master structure + * @spi: Pointer to the spi_device structure + * @transfer: Pointer to the spi_transfer structure which provides + * information about next transfer parameters + * + * This function fills the TX FIFO, starts the SPI transfer and + * returns a positive transfer count so that core will wait for completion. + * + * Return: Number of bytes transferred in the last transfer + */ +static int cdns_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *transfer) +{ + struct cdns_spi *xspi = spi_master_get_devdata(master); + + xspi->txbuf = transfer->tx_buf; + xspi->rxbuf = transfer->rx_buf; + xspi->tx_bytes = transfer->len; + xspi->rx_bytes = transfer->len; + + cdns_spi_setup_transfer(spi, transfer); + cdns_spi_fill_tx_fifo(xspi); + spi_transfer_delay_exec(transfer); + + cdns_spi_write(xspi, CDNS_SPI_IER, CDNS_SPI_IXR_DEFAULT); + return transfer->len; +} + +/** + * cdns_prepare_transfer_hardware - Prepares hardware for transfer. + * @master: Pointer to the spi_master structure which provides + * information about the controller. + * + * This function enables SPI master controller. + * + * Return: 0 always + */ +static int cdns_prepare_transfer_hardware(struct spi_master *master) +{ + struct cdns_spi *xspi = spi_master_get_devdata(master); + + cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_ENABLE); + + return 0; +} + +/** + * cdns_unprepare_transfer_hardware - Relaxes hardware after transfer + * @master: Pointer to the spi_master structure which provides + * information about the controller. + * + * This function disables the SPI master controller when no slave selected. + * + * Return: 0 always + */ +static int cdns_unprepare_transfer_hardware(struct spi_master *master) +{ + struct cdns_spi *xspi = spi_master_get_devdata(master); + u32 ctrl_reg; + + /* Disable the SPI if slave is deselected */ + ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR); + ctrl_reg = (ctrl_reg & CDNS_SPI_CR_SSCTRL) >> CDNS_SPI_SS_SHIFT; + if (ctrl_reg == CDNS_SPI_NOSS) + cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_DISABLE); + + return 0; +} + +/** + * cdns_spi_detect_fifo_depth - Detect the FIFO depth of the hardware + * @xspi: Pointer to the cdns_spi structure + * + * The depth of the TX FIFO is a synthesis configuration parameter of the SPI + * IP. The FIFO threshold register is sized so that its maximum value can be the + * FIFO size - 1. This is used to detect the size of the FIFO. + */ +static void cdns_spi_detect_fifo_depth(struct cdns_spi *xspi) +{ + /* The MSBs will get truncated giving us the size of the FIFO */ + cdns_spi_write(xspi, CDNS_SPI_THLD, 0xffff); + xspi->tx_fifo_depth = cdns_spi_read(xspi, CDNS_SPI_THLD) + 1; + + /* Reset to default */ + cdns_spi_write(xspi, CDNS_SPI_THLD, 0x1); +} + +/** + * cdns_spi_probe - Probe method for the SPI driver + * @pdev: Pointer to the platform_device structure + * + * This function initializes the driver data structures and the hardware. + * + * Return: 0 on success and error value on error + */ +static int cdns_spi_probe(struct platform_device *pdev) +{ + int ret = 0, irq; + struct spi_master *master; + struct cdns_spi *xspi; + u32 num_cs; + + master = spi_alloc_master(&pdev->dev, sizeof(*xspi)); + if (!master) + return -ENOMEM; + + xspi = spi_master_get_devdata(master); + master->dev.of_node = pdev->dev.of_node; + platform_set_drvdata(pdev, master); + + xspi->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(xspi->regs)) { + ret = PTR_ERR(xspi->regs); + goto remove_master; + } + + xspi->pclk = devm_clk_get(&pdev->dev, "pclk"); + if (IS_ERR(xspi->pclk)) { + dev_err(&pdev->dev, "pclk clock not found.\n"); + ret = PTR_ERR(xspi->pclk); + goto remove_master; + } + + xspi->ref_clk = devm_clk_get(&pdev->dev, "ref_clk"); + if (IS_ERR(xspi->ref_clk)) { + dev_err(&pdev->dev, "ref_clk clock not found.\n"); + ret = PTR_ERR(xspi->ref_clk); + goto remove_master; + } + + ret = clk_prepare_enable(xspi->pclk); + if (ret) { + dev_err(&pdev->dev, "Unable to enable APB clock.\n"); + goto remove_master; + } + + ret = clk_prepare_enable(xspi->ref_clk); + if (ret) { + dev_err(&pdev->dev, "Unable to enable device clock.\n"); + goto clk_dis_apb; + } + + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT); + pm_runtime_get_noresume(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + ret = of_property_read_u32(pdev->dev.of_node, "num-cs", &num_cs); + if (ret < 0) + master->num_chipselect = CDNS_SPI_DEFAULT_NUM_CS; + else + master->num_chipselect = num_cs; + + ret = of_property_read_u32(pdev->dev.of_node, "is-decoded-cs", + &xspi->is_decoded_cs); + if (ret < 0) + xspi->is_decoded_cs = 0; + + cdns_spi_detect_fifo_depth(xspi); + + /* SPI controller initializations */ + cdns_spi_init_hw(xspi); + + irq = platform_get_irq(pdev, 0); + if (irq <= 0) { + ret = -ENXIO; + goto clk_dis_all; + } + + ret = devm_request_irq(&pdev->dev, irq, cdns_spi_irq, + 0, pdev->name, master); + if (ret != 0) { + ret = -ENXIO; + dev_err(&pdev->dev, "request_irq failed\n"); + goto clk_dis_all; + } + + master->use_gpio_descriptors = true; + master->prepare_transfer_hardware = cdns_prepare_transfer_hardware; + master->prepare_message = cdns_prepare_message; + master->transfer_one = cdns_transfer_one; + master->unprepare_transfer_hardware = cdns_unprepare_transfer_hardware; + master->set_cs = cdns_spi_chipselect; + master->auto_runtime_pm = true; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + + xspi->clk_rate = clk_get_rate(xspi->ref_clk); + /* Set to default valid value */ + master->max_speed_hz = xspi->clk_rate / 4; + xspi->speed_hz = master->max_speed_hz; + + master->bits_per_word_mask = SPI_BPW_MASK(8); + + pm_runtime_mark_last_busy(&pdev->dev); + pm_runtime_put_autosuspend(&pdev->dev); + + ret = spi_register_master(master); + if (ret) { + dev_err(&pdev->dev, "spi_register_master failed\n"); + goto clk_dis_all; + } + + return ret; + +clk_dis_all: + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_disable(&pdev->dev); + clk_disable_unprepare(xspi->ref_clk); +clk_dis_apb: + clk_disable_unprepare(xspi->pclk); +remove_master: + spi_master_put(master); + return ret; +} + +/** + * cdns_spi_remove - Remove method for the SPI driver + * @pdev: Pointer to the platform_device structure + * + * This function is called if a device is physically removed from the system or + * if the driver module is being unloaded. It frees all resources allocated to + * the device. + * + * Return: 0 on success and error value on error + */ +static int cdns_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct cdns_spi *xspi = spi_master_get_devdata(master); + + cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_DISABLE); + + clk_disable_unprepare(xspi->ref_clk); + clk_disable_unprepare(xspi->pclk); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_disable(&pdev->dev); + + spi_unregister_master(master); + + return 0; +} + +/** + * cdns_spi_suspend - Suspend method for the SPI driver + * @dev: Address of the platform_device structure + * + * This function disables the SPI controller and + * changes the driver state to "suspend" + * + * Return: 0 on success and error value on error + */ +static int __maybe_unused cdns_spi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + + return spi_master_suspend(master); +} + +/** + * cdns_spi_resume - Resume method for the SPI driver + * @dev: Address of the platform_device structure + * + * This function changes the driver state to "ready" + * + * Return: 0 on success and error value on error + */ +static int __maybe_unused cdns_spi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct cdns_spi *xspi = spi_master_get_devdata(master); + + cdns_spi_init_hw(xspi); + return spi_master_resume(master); +} + +/** + * cdns_spi_runtime_resume - Runtime resume method for the SPI driver + * @dev: Address of the platform_device structure + * + * This function enables the clocks + * + * Return: 0 on success and error value on error + */ +static int __maybe_unused cdns_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct cdns_spi *xspi = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(xspi->pclk); + if (ret) { + dev_err(dev, "Cannot enable APB clock.\n"); + return ret; + } + + ret = clk_prepare_enable(xspi->ref_clk); + if (ret) { + dev_err(dev, "Cannot enable device clock.\n"); + clk_disable_unprepare(xspi->pclk); + return ret; + } + return 0; +} + +/** + * cdns_spi_runtime_suspend - Runtime suspend method for the SPI driver + * @dev: Address of the platform_device structure + * + * This function disables the clocks + * + * Return: Always 0 + */ +static int __maybe_unused cdns_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct cdns_spi *xspi = spi_master_get_devdata(master); + + clk_disable_unprepare(xspi->ref_clk); + clk_disable_unprepare(xspi->pclk); + + return 0; +} + +static const struct dev_pm_ops cdns_spi_dev_pm_ops = { + SET_RUNTIME_PM_OPS(cdns_spi_runtime_suspend, + cdns_spi_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(cdns_spi_suspend, cdns_spi_resume) +}; + +static const struct of_device_id cdns_spi_of_match[] = { + { .compatible = "xlnx,zynq-spi-r1p6" }, + { .compatible = "cdns,spi-r1p6" }, + { /* end of table */ } +}; +MODULE_DEVICE_TABLE(of, cdns_spi_of_match); + +/* cdns_spi_driver - This structure defines the SPI subsystem platform driver */ +static struct platform_driver cdns_spi_driver = { + .probe = cdns_spi_probe, + .remove = cdns_spi_remove, + .driver = { + .name = CDNS_SPI_NAME, + .of_match_table = cdns_spi_of_match, + .pm = &cdns_spi_dev_pm_ops, + }, +}; + +module_platform_driver(cdns_spi_driver); + +MODULE_AUTHOR("Xilinx, Inc."); +MODULE_DESCRIPTION("Cadence SPI driver"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3