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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/spi/spi-armada-3700.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/spi/spi-armada-3700.c')
-rw-r--r--drivers/spi/spi-armada-3700.c935
1 files changed, 935 insertions, 0 deletions
diff --git a/drivers/spi/spi-armada-3700.c b/drivers/spi/spi-armada-3700.c
new file mode 100644
index 000000000..9df9fc40b
--- /dev/null
+++ b/drivers/spi/spi-armada-3700.c
@@ -0,0 +1,935 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Marvell Armada-3700 SPI controller driver
+ *
+ * Copyright (C) 2016 Marvell Ltd.
+ *
+ * Author: Wilson Ding <dingwei@marvell.com>
+ * Author: Romain Perier <romain.perier@free-electrons.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/spi/spi.h>
+
+#define DRIVER_NAME "armada_3700_spi"
+
+#define A3700_SPI_MAX_SPEED_HZ 100000000
+#define A3700_SPI_MAX_PRESCALE 30
+#define A3700_SPI_TIMEOUT 10
+
+/* SPI Register Offest */
+#define A3700_SPI_IF_CTRL_REG 0x00
+#define A3700_SPI_IF_CFG_REG 0x04
+#define A3700_SPI_DATA_OUT_REG 0x08
+#define A3700_SPI_DATA_IN_REG 0x0C
+#define A3700_SPI_IF_INST_REG 0x10
+#define A3700_SPI_IF_ADDR_REG 0x14
+#define A3700_SPI_IF_RMODE_REG 0x18
+#define A3700_SPI_IF_HDR_CNT_REG 0x1C
+#define A3700_SPI_IF_DIN_CNT_REG 0x20
+#define A3700_SPI_IF_TIME_REG 0x24
+#define A3700_SPI_INT_STAT_REG 0x28
+#define A3700_SPI_INT_MASK_REG 0x2C
+
+/* A3700_SPI_IF_CTRL_REG */
+#define A3700_SPI_EN BIT(16)
+#define A3700_SPI_ADDR_NOT_CONFIG BIT(12)
+#define A3700_SPI_WFIFO_OVERFLOW BIT(11)
+#define A3700_SPI_WFIFO_UNDERFLOW BIT(10)
+#define A3700_SPI_RFIFO_OVERFLOW BIT(9)
+#define A3700_SPI_RFIFO_UNDERFLOW BIT(8)
+#define A3700_SPI_WFIFO_FULL BIT(7)
+#define A3700_SPI_WFIFO_EMPTY BIT(6)
+#define A3700_SPI_RFIFO_FULL BIT(5)
+#define A3700_SPI_RFIFO_EMPTY BIT(4)
+#define A3700_SPI_WFIFO_RDY BIT(3)
+#define A3700_SPI_RFIFO_RDY BIT(2)
+#define A3700_SPI_XFER_RDY BIT(1)
+#define A3700_SPI_XFER_DONE BIT(0)
+
+/* A3700_SPI_IF_CFG_REG */
+#define A3700_SPI_WFIFO_THRS BIT(28)
+#define A3700_SPI_RFIFO_THRS BIT(24)
+#define A3700_SPI_AUTO_CS BIT(20)
+#define A3700_SPI_DMA_RD_EN BIT(18)
+#define A3700_SPI_FIFO_MODE BIT(17)
+#define A3700_SPI_SRST BIT(16)
+#define A3700_SPI_XFER_START BIT(15)
+#define A3700_SPI_XFER_STOP BIT(14)
+#define A3700_SPI_INST_PIN BIT(13)
+#define A3700_SPI_ADDR_PIN BIT(12)
+#define A3700_SPI_DATA_PIN1 BIT(11)
+#define A3700_SPI_DATA_PIN0 BIT(10)
+#define A3700_SPI_FIFO_FLUSH BIT(9)
+#define A3700_SPI_RW_EN BIT(8)
+#define A3700_SPI_CLK_POL BIT(7)
+#define A3700_SPI_CLK_PHA BIT(6)
+#define A3700_SPI_BYTE_LEN BIT(5)
+#define A3700_SPI_CLK_PRESCALE BIT(0)
+#define A3700_SPI_CLK_PRESCALE_MASK (0x1f)
+#define A3700_SPI_CLK_EVEN_OFFS (0x10)
+
+#define A3700_SPI_WFIFO_THRS_BIT 28
+#define A3700_SPI_RFIFO_THRS_BIT 24
+#define A3700_SPI_FIFO_THRS_MASK 0x7
+
+#define A3700_SPI_DATA_PIN_MASK 0x3
+
+/* A3700_SPI_IF_HDR_CNT_REG */
+#define A3700_SPI_DUMMY_CNT_BIT 12
+#define A3700_SPI_DUMMY_CNT_MASK 0x7
+#define A3700_SPI_RMODE_CNT_BIT 8
+#define A3700_SPI_RMODE_CNT_MASK 0x3
+#define A3700_SPI_ADDR_CNT_BIT 4
+#define A3700_SPI_ADDR_CNT_MASK 0x7
+#define A3700_SPI_INSTR_CNT_BIT 0
+#define A3700_SPI_INSTR_CNT_MASK 0x3
+
+/* A3700_SPI_IF_TIME_REG */
+#define A3700_SPI_CLK_CAPT_EDGE BIT(7)
+
+struct a3700_spi {
+ struct spi_master *master;
+ void __iomem *base;
+ struct clk *clk;
+ unsigned int irq;
+ unsigned int flags;
+ bool xmit_data;
+ const u8 *tx_buf;
+ u8 *rx_buf;
+ size_t buf_len;
+ u8 byte_len;
+ u32 wait_mask;
+ struct completion done;
+};
+
+static u32 spireg_read(struct a3700_spi *a3700_spi, u32 offset)
+{
+ return readl(a3700_spi->base + offset);
+}
+
+static void spireg_write(struct a3700_spi *a3700_spi, u32 offset, u32 data)
+{
+ writel(data, a3700_spi->base + offset);
+}
+
+static void a3700_spi_auto_cs_unset(struct a3700_spi *a3700_spi)
+{
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val &= ~A3700_SPI_AUTO_CS;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+}
+
+static void a3700_spi_activate_cs(struct a3700_spi *a3700_spi, unsigned int cs)
+{
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG);
+ val |= (A3700_SPI_EN << cs);
+ spireg_write(a3700_spi, A3700_SPI_IF_CTRL_REG, val);
+}
+
+static void a3700_spi_deactivate_cs(struct a3700_spi *a3700_spi,
+ unsigned int cs)
+{
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG);
+ val &= ~(A3700_SPI_EN << cs);
+ spireg_write(a3700_spi, A3700_SPI_IF_CTRL_REG, val);
+}
+
+static int a3700_spi_pin_mode_set(struct a3700_spi *a3700_spi,
+ unsigned int pin_mode, bool receiving)
+{
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val &= ~(A3700_SPI_INST_PIN | A3700_SPI_ADDR_PIN);
+ val &= ~(A3700_SPI_DATA_PIN0 | A3700_SPI_DATA_PIN1);
+
+ switch (pin_mode) {
+ case SPI_NBITS_SINGLE:
+ break;
+ case SPI_NBITS_DUAL:
+ val |= A3700_SPI_DATA_PIN0;
+ break;
+ case SPI_NBITS_QUAD:
+ val |= A3700_SPI_DATA_PIN1;
+ /* RX during address reception uses 4-pin */
+ if (receiving)
+ val |= A3700_SPI_ADDR_PIN;
+ break;
+ default:
+ dev_err(&a3700_spi->master->dev, "wrong pin mode %u", pin_mode);
+ return -EINVAL;
+ }
+
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+
+ return 0;
+}
+
+static void a3700_spi_fifo_mode_set(struct a3700_spi *a3700_spi, bool enable)
+{
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ if (enable)
+ val |= A3700_SPI_FIFO_MODE;
+ else
+ val &= ~A3700_SPI_FIFO_MODE;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+}
+
+static void a3700_spi_mode_set(struct a3700_spi *a3700_spi,
+ unsigned int mode_bits)
+{
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+
+ if (mode_bits & SPI_CPOL)
+ val |= A3700_SPI_CLK_POL;
+ else
+ val &= ~A3700_SPI_CLK_POL;
+
+ if (mode_bits & SPI_CPHA)
+ val |= A3700_SPI_CLK_PHA;
+ else
+ val &= ~A3700_SPI_CLK_PHA;
+
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+}
+
+static void a3700_spi_clock_set(struct a3700_spi *a3700_spi,
+ unsigned int speed_hz)
+{
+ u32 val;
+ u32 prescale;
+
+ prescale = DIV_ROUND_UP(clk_get_rate(a3700_spi->clk), speed_hz);
+
+ /* For prescaler values over 15, we can only set it by steps of 2.
+ * Starting from A3700_SPI_CLK_EVEN_OFFS, we set values from 0 up to
+ * 30. We only use this range from 16 to 30.
+ */
+ if (prescale > 15)
+ prescale = A3700_SPI_CLK_EVEN_OFFS + DIV_ROUND_UP(prescale, 2);
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val = val & ~A3700_SPI_CLK_PRESCALE_MASK;
+
+ val = val | (prescale & A3700_SPI_CLK_PRESCALE_MASK);
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+
+ if (prescale <= 2) {
+ val = spireg_read(a3700_spi, A3700_SPI_IF_TIME_REG);
+ val |= A3700_SPI_CLK_CAPT_EDGE;
+ spireg_write(a3700_spi, A3700_SPI_IF_TIME_REG, val);
+ }
+}
+
+static void a3700_spi_bytelen_set(struct a3700_spi *a3700_spi, unsigned int len)
+{
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ if (len == 4)
+ val |= A3700_SPI_BYTE_LEN;
+ else
+ val &= ~A3700_SPI_BYTE_LEN;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+
+ a3700_spi->byte_len = len;
+}
+
+static int a3700_spi_fifo_flush(struct a3700_spi *a3700_spi)
+{
+ int timeout = A3700_SPI_TIMEOUT;
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val |= A3700_SPI_FIFO_FLUSH;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+
+ while (--timeout) {
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ if (!(val & A3700_SPI_FIFO_FLUSH))
+ return 0;
+ udelay(1);
+ }
+
+ return -ETIMEDOUT;
+}
+
+static void a3700_spi_init(struct a3700_spi *a3700_spi)
+{
+ struct spi_master *master = a3700_spi->master;
+ u32 val;
+ int i;
+
+ /* Reset SPI unit */
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val |= A3700_SPI_SRST;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+
+ udelay(A3700_SPI_TIMEOUT);
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val &= ~A3700_SPI_SRST;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+
+ /* Disable AUTO_CS and deactivate all chip-selects */
+ a3700_spi_auto_cs_unset(a3700_spi);
+ for (i = 0; i < master->num_chipselect; i++)
+ a3700_spi_deactivate_cs(a3700_spi, i);
+
+ /* Enable FIFO mode */
+ a3700_spi_fifo_mode_set(a3700_spi, true);
+
+ /* Set SPI mode */
+ a3700_spi_mode_set(a3700_spi, master->mode_bits);
+
+ /* Reset counters */
+ spireg_write(a3700_spi, A3700_SPI_IF_HDR_CNT_REG, 0);
+ spireg_write(a3700_spi, A3700_SPI_IF_DIN_CNT_REG, 0);
+
+ /* Mask the interrupts and clear cause bits */
+ spireg_write(a3700_spi, A3700_SPI_INT_MASK_REG, 0);
+ spireg_write(a3700_spi, A3700_SPI_INT_STAT_REG, ~0U);
+}
+
+static irqreturn_t a3700_spi_interrupt(int irq, void *dev_id)
+{
+ struct spi_master *master = dev_id;
+ struct a3700_spi *a3700_spi;
+ u32 cause;
+
+ a3700_spi = spi_master_get_devdata(master);
+
+ /* Get interrupt causes */
+ cause = spireg_read(a3700_spi, A3700_SPI_INT_STAT_REG);
+
+ if (!cause || !(a3700_spi->wait_mask & cause))
+ return IRQ_NONE;
+
+ /* mask and acknowledge the SPI interrupts */
+ spireg_write(a3700_spi, A3700_SPI_INT_MASK_REG, 0);
+ spireg_write(a3700_spi, A3700_SPI_INT_STAT_REG, cause);
+
+ /* Wake up the transfer */
+ complete(&a3700_spi->done);
+
+ return IRQ_HANDLED;
+}
+
+static bool a3700_spi_wait_completion(struct spi_device *spi)
+{
+ struct a3700_spi *a3700_spi;
+ unsigned int timeout;
+ unsigned int ctrl_reg;
+ unsigned long timeout_jiffies;
+
+ a3700_spi = spi_master_get_devdata(spi->master);
+
+ /* SPI interrupt is edge-triggered, which means an interrupt will
+ * be generated only when detecting a specific status bit changed
+ * from '0' to '1'. So when we start waiting for a interrupt, we
+ * need to check status bit in control reg first, if it is already 1,
+ * then we do not need to wait for interrupt
+ */
+ ctrl_reg = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG);
+ if (a3700_spi->wait_mask & ctrl_reg)
+ return true;
+
+ reinit_completion(&a3700_spi->done);
+
+ spireg_write(a3700_spi, A3700_SPI_INT_MASK_REG,
+ a3700_spi->wait_mask);
+
+ timeout_jiffies = msecs_to_jiffies(A3700_SPI_TIMEOUT);
+ timeout = wait_for_completion_timeout(&a3700_spi->done,
+ timeout_jiffies);
+
+ a3700_spi->wait_mask = 0;
+
+ if (timeout)
+ return true;
+
+ /* there might be the case that right after we checked the
+ * status bits in this routine and before start to wait for
+ * interrupt by wait_for_completion_timeout, the interrupt
+ * happens, to avoid missing it we need to double check
+ * status bits in control reg, if it is already 1, then
+ * consider that we have the interrupt successfully and
+ * return true.
+ */
+ ctrl_reg = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG);
+ if (a3700_spi->wait_mask & ctrl_reg)
+ return true;
+
+ spireg_write(a3700_spi, A3700_SPI_INT_MASK_REG, 0);
+
+ /* Timeout was reached */
+ return false;
+}
+
+static bool a3700_spi_transfer_wait(struct spi_device *spi,
+ unsigned int bit_mask)
+{
+ struct a3700_spi *a3700_spi;
+
+ a3700_spi = spi_master_get_devdata(spi->master);
+ a3700_spi->wait_mask = bit_mask;
+
+ return a3700_spi_wait_completion(spi);
+}
+
+static void a3700_spi_fifo_thres_set(struct a3700_spi *a3700_spi,
+ unsigned int bytes)
+{
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val &= ~(A3700_SPI_FIFO_THRS_MASK << A3700_SPI_RFIFO_THRS_BIT);
+ val |= (bytes - 1) << A3700_SPI_RFIFO_THRS_BIT;
+ val &= ~(A3700_SPI_FIFO_THRS_MASK << A3700_SPI_WFIFO_THRS_BIT);
+ val |= (7 - bytes) << A3700_SPI_WFIFO_THRS_BIT;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+}
+
+static void a3700_spi_transfer_setup(struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct a3700_spi *a3700_spi;
+
+ a3700_spi = spi_master_get_devdata(spi->master);
+
+ a3700_spi_clock_set(a3700_spi, xfer->speed_hz);
+
+ /* Use 4 bytes long transfers. Each transfer method has its way to deal
+ * with the remaining bytes for non 4-bytes aligned transfers.
+ */
+ a3700_spi_bytelen_set(a3700_spi, 4);
+
+ /* Initialize the working buffers */
+ a3700_spi->tx_buf = xfer->tx_buf;
+ a3700_spi->rx_buf = xfer->rx_buf;
+ a3700_spi->buf_len = xfer->len;
+}
+
+static void a3700_spi_set_cs(struct spi_device *spi, bool enable)
+{
+ struct a3700_spi *a3700_spi = spi_master_get_devdata(spi->master);
+
+ if (!enable)
+ a3700_spi_activate_cs(a3700_spi, spi->chip_select);
+ else
+ a3700_spi_deactivate_cs(a3700_spi, spi->chip_select);
+}
+
+static void a3700_spi_header_set(struct a3700_spi *a3700_spi)
+{
+ unsigned int addr_cnt;
+ u32 val = 0;
+
+ /* Clear the header registers */
+ spireg_write(a3700_spi, A3700_SPI_IF_INST_REG, 0);
+ spireg_write(a3700_spi, A3700_SPI_IF_ADDR_REG, 0);
+ spireg_write(a3700_spi, A3700_SPI_IF_RMODE_REG, 0);
+ spireg_write(a3700_spi, A3700_SPI_IF_HDR_CNT_REG, 0);
+
+ /* Set header counters */
+ if (a3700_spi->tx_buf) {
+ /*
+ * when tx data is not 4 bytes aligned, there will be unexpected
+ * bytes out of SPI output register, since it always shifts out
+ * as whole 4 bytes. This might cause incorrect transaction with
+ * some devices. To avoid that, use SPI header count feature to
+ * transfer up to 3 bytes of data first, and then make the rest
+ * of data 4-byte aligned.
+ */
+ addr_cnt = a3700_spi->buf_len % 4;
+ if (addr_cnt) {
+ val = (addr_cnt & A3700_SPI_ADDR_CNT_MASK)
+ << A3700_SPI_ADDR_CNT_BIT;
+ spireg_write(a3700_spi, A3700_SPI_IF_HDR_CNT_REG, val);
+
+ /* Update the buffer length to be transferred */
+ a3700_spi->buf_len -= addr_cnt;
+
+ /* transfer 1~3 bytes through address count */
+ val = 0;
+ while (addr_cnt--) {
+ val = (val << 8) | a3700_spi->tx_buf[0];
+ a3700_spi->tx_buf++;
+ }
+ spireg_write(a3700_spi, A3700_SPI_IF_ADDR_REG, val);
+ }
+ }
+}
+
+static int a3700_is_wfifo_full(struct a3700_spi *a3700_spi)
+{
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG);
+ return (val & A3700_SPI_WFIFO_FULL);
+}
+
+static int a3700_spi_fifo_write(struct a3700_spi *a3700_spi)
+{
+ u32 val;
+
+ while (!a3700_is_wfifo_full(a3700_spi) && a3700_spi->buf_len) {
+ val = *(u32 *)a3700_spi->tx_buf;
+ spireg_write(a3700_spi, A3700_SPI_DATA_OUT_REG, cpu_to_le32(val));
+ a3700_spi->buf_len -= 4;
+ a3700_spi->tx_buf += 4;
+ }
+
+ return 0;
+}
+
+static int a3700_is_rfifo_empty(struct a3700_spi *a3700_spi)
+{
+ u32 val = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG);
+
+ return (val & A3700_SPI_RFIFO_EMPTY);
+}
+
+static int a3700_spi_fifo_read(struct a3700_spi *a3700_spi)
+{
+ u32 val;
+
+ while (!a3700_is_rfifo_empty(a3700_spi) && a3700_spi->buf_len) {
+ val = spireg_read(a3700_spi, A3700_SPI_DATA_IN_REG);
+ if (a3700_spi->buf_len >= 4) {
+ val = le32_to_cpu(val);
+ memcpy(a3700_spi->rx_buf, &val, 4);
+
+ a3700_spi->buf_len -= 4;
+ a3700_spi->rx_buf += 4;
+ } else {
+ /*
+ * When remain bytes is not larger than 4, we should
+ * avoid memory overwriting and just write the left rx
+ * buffer bytes.
+ */
+ while (a3700_spi->buf_len) {
+ *a3700_spi->rx_buf = val & 0xff;
+ val >>= 8;
+
+ a3700_spi->buf_len--;
+ a3700_spi->rx_buf++;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static void a3700_spi_transfer_abort_fifo(struct a3700_spi *a3700_spi)
+{
+ int timeout = A3700_SPI_TIMEOUT;
+ u32 val;
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val |= A3700_SPI_XFER_STOP;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+
+ while (--timeout) {
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ if (!(val & A3700_SPI_XFER_START))
+ break;
+ udelay(1);
+ }
+
+ a3700_spi_fifo_flush(a3700_spi);
+
+ val &= ~A3700_SPI_XFER_STOP;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+}
+
+static int a3700_spi_prepare_message(struct spi_master *master,
+ struct spi_message *message)
+{
+ struct a3700_spi *a3700_spi = spi_master_get_devdata(master);
+ struct spi_device *spi = message->spi;
+ int ret;
+
+ ret = clk_enable(a3700_spi->clk);
+ if (ret) {
+ dev_err(&spi->dev, "failed to enable clk with error %d\n", ret);
+ return ret;
+ }
+
+ /* Flush the FIFOs */
+ ret = a3700_spi_fifo_flush(a3700_spi);
+ if (ret)
+ return ret;
+
+ a3700_spi_mode_set(a3700_spi, spi->mode);
+
+ return 0;
+}
+
+static int a3700_spi_transfer_one_fifo(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct a3700_spi *a3700_spi = spi_master_get_devdata(master);
+ int ret = 0, timeout = A3700_SPI_TIMEOUT;
+ unsigned int nbits = 0, byte_len;
+ u32 val;
+
+ /* Make sure we use FIFO mode */
+ a3700_spi_fifo_mode_set(a3700_spi, true);
+
+ /* Configure FIFO thresholds */
+ byte_len = xfer->bits_per_word >> 3;
+ a3700_spi_fifo_thres_set(a3700_spi, byte_len);
+
+ if (xfer->tx_buf)
+ nbits = xfer->tx_nbits;
+ else if (xfer->rx_buf)
+ nbits = xfer->rx_nbits;
+
+ a3700_spi_pin_mode_set(a3700_spi, nbits, xfer->rx_buf ? true : false);
+
+ /* Flush the FIFOs */
+ a3700_spi_fifo_flush(a3700_spi);
+
+ /* Transfer first bytes of data when buffer is not 4-byte aligned */
+ a3700_spi_header_set(a3700_spi);
+
+ if (xfer->rx_buf) {
+ /* Clear WFIFO, since it's last 2 bytes are shifted out during
+ * a read operation
+ */
+ spireg_write(a3700_spi, A3700_SPI_DATA_OUT_REG, 0);
+
+ /* Set read data length */
+ spireg_write(a3700_spi, A3700_SPI_IF_DIN_CNT_REG,
+ a3700_spi->buf_len);
+ /* Start READ transfer */
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val &= ~A3700_SPI_RW_EN;
+ val |= A3700_SPI_XFER_START;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+ } else if (xfer->tx_buf) {
+ /* Start Write transfer */
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val |= (A3700_SPI_XFER_START | A3700_SPI_RW_EN);
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+
+ /*
+ * If there are data to be written to the SPI device, xmit_data
+ * flag is set true; otherwise the instruction in SPI_INSTR does
+ * not require data to be written to the SPI device, then
+ * xmit_data flag is set false.
+ */
+ a3700_spi->xmit_data = (a3700_spi->buf_len != 0);
+ }
+
+ while (a3700_spi->buf_len) {
+ if (a3700_spi->tx_buf) {
+ /* Wait wfifo ready */
+ if (!a3700_spi_transfer_wait(spi,
+ A3700_SPI_WFIFO_RDY)) {
+ dev_err(&spi->dev,
+ "wait wfifo ready timed out\n");
+ ret = -ETIMEDOUT;
+ goto error;
+ }
+ /* Fill up the wfifo */
+ ret = a3700_spi_fifo_write(a3700_spi);
+ if (ret)
+ goto error;
+ } else if (a3700_spi->rx_buf) {
+ /* Wait rfifo ready */
+ if (!a3700_spi_transfer_wait(spi,
+ A3700_SPI_RFIFO_RDY)) {
+ dev_err(&spi->dev,
+ "wait rfifo ready timed out\n");
+ ret = -ETIMEDOUT;
+ goto error;
+ }
+ /* Drain out the rfifo */
+ ret = a3700_spi_fifo_read(a3700_spi);
+ if (ret)
+ goto error;
+ }
+ }
+
+ /*
+ * Stop a write transfer in fifo mode:
+ * - wait all the bytes in wfifo to be shifted out
+ * - set XFER_STOP bit
+ * - wait XFER_START bit clear
+ * - clear XFER_STOP bit
+ * Stop a read transfer in fifo mode:
+ * - the hardware is to reset the XFER_START bit
+ * after the number of bytes indicated in DIN_CNT
+ * register
+ * - just wait XFER_START bit clear
+ */
+ if (a3700_spi->tx_buf) {
+ if (a3700_spi->xmit_data) {
+ /*
+ * If there are data written to the SPI device, wait
+ * until SPI_WFIFO_EMPTY is 1 to wait for all data to
+ * transfer out of write FIFO.
+ */
+ if (!a3700_spi_transfer_wait(spi,
+ A3700_SPI_WFIFO_EMPTY)) {
+ dev_err(&spi->dev, "wait wfifo empty timed out\n");
+ return -ETIMEDOUT;
+ }
+ }
+
+ if (!a3700_spi_transfer_wait(spi, A3700_SPI_XFER_RDY)) {
+ dev_err(&spi->dev, "wait xfer ready timed out\n");
+ return -ETIMEDOUT;
+ }
+
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ val |= A3700_SPI_XFER_STOP;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+ }
+
+ while (--timeout) {
+ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
+ if (!(val & A3700_SPI_XFER_START))
+ break;
+ udelay(1);
+ }
+
+ if (timeout == 0) {
+ dev_err(&spi->dev, "wait transfer start clear timed out\n");
+ ret = -ETIMEDOUT;
+ goto error;
+ }
+
+ val &= ~A3700_SPI_XFER_STOP;
+ spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
+ goto out;
+
+error:
+ a3700_spi_transfer_abort_fifo(a3700_spi);
+out:
+ spi_finalize_current_transfer(master);
+
+ return ret;
+}
+
+static int a3700_spi_transfer_one_full_duplex(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct a3700_spi *a3700_spi = spi_master_get_devdata(master);
+ u32 val;
+
+ /* Disable FIFO mode */
+ a3700_spi_fifo_mode_set(a3700_spi, false);
+
+ while (a3700_spi->buf_len) {
+
+ /* When we have less than 4 bytes to transfer, switch to 1 byte
+ * mode. This is reset after each transfer
+ */
+ if (a3700_spi->buf_len < 4)
+ a3700_spi_bytelen_set(a3700_spi, 1);
+
+ if (a3700_spi->byte_len == 1)
+ val = *a3700_spi->tx_buf;
+ else
+ val = *(u32 *)a3700_spi->tx_buf;
+
+ spireg_write(a3700_spi, A3700_SPI_DATA_OUT_REG, val);
+
+ /* Wait for all the data to be shifted in / out */
+ while (!(spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG) &
+ A3700_SPI_XFER_DONE))
+ cpu_relax();
+
+ val = spireg_read(a3700_spi, A3700_SPI_DATA_IN_REG);
+
+ memcpy(a3700_spi->rx_buf, &val, a3700_spi->byte_len);
+
+ a3700_spi->buf_len -= a3700_spi->byte_len;
+ a3700_spi->tx_buf += a3700_spi->byte_len;
+ a3700_spi->rx_buf += a3700_spi->byte_len;
+
+ }
+
+ spi_finalize_current_transfer(master);
+
+ return 0;
+}
+
+static int a3700_spi_transfer_one(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ a3700_spi_transfer_setup(spi, xfer);
+
+ if (xfer->tx_buf && xfer->rx_buf)
+ return a3700_spi_transfer_one_full_duplex(master, spi, xfer);
+
+ return a3700_spi_transfer_one_fifo(master, spi, xfer);
+}
+
+static int a3700_spi_unprepare_message(struct spi_master *master,
+ struct spi_message *message)
+{
+ struct a3700_spi *a3700_spi = spi_master_get_devdata(master);
+
+ clk_disable(a3700_spi->clk);
+
+ return 0;
+}
+
+static const struct of_device_id a3700_spi_dt_ids[] = {
+ { .compatible = "marvell,armada-3700-spi", .data = NULL },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, a3700_spi_dt_ids);
+
+static int a3700_spi_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *of_node = dev->of_node;
+ struct spi_master *master;
+ struct a3700_spi *spi;
+ u32 num_cs = 0;
+ int irq, ret = 0;
+
+ master = spi_alloc_master(dev, sizeof(*spi));
+ if (!master) {
+ dev_err(dev, "master allocation failed\n");
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ if (of_property_read_u32(of_node, "num-cs", &num_cs)) {
+ dev_err(dev, "could not find num-cs\n");
+ ret = -ENXIO;
+ goto error;
+ }
+
+ master->bus_num = pdev->id;
+ master->dev.of_node = of_node;
+ master->mode_bits = SPI_MODE_3;
+ master->num_chipselect = num_cs;
+ master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(32);
+ master->prepare_message = a3700_spi_prepare_message;
+ master->transfer_one = a3700_spi_transfer_one;
+ master->unprepare_message = a3700_spi_unprepare_message;
+ master->set_cs = a3700_spi_set_cs;
+ master->mode_bits |= (SPI_RX_DUAL | SPI_TX_DUAL |
+ SPI_RX_QUAD | SPI_TX_QUAD);
+
+ platform_set_drvdata(pdev, master);
+
+ spi = spi_master_get_devdata(master);
+
+ spi->master = master;
+
+ spi->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(spi->base)) {
+ ret = PTR_ERR(spi->base);
+ goto error;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ ret = -ENXIO;
+ goto error;
+ }
+ spi->irq = irq;
+
+ init_completion(&spi->done);
+
+ spi->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(spi->clk)) {
+ dev_err(dev, "could not find clk: %ld\n", PTR_ERR(spi->clk));
+ goto error;
+ }
+
+ ret = clk_prepare(spi->clk);
+ if (ret) {
+ dev_err(dev, "could not prepare clk: %d\n", ret);
+ goto error;
+ }
+
+ master->max_speed_hz = min_t(unsigned long, A3700_SPI_MAX_SPEED_HZ,
+ clk_get_rate(spi->clk));
+ master->min_speed_hz = DIV_ROUND_UP(clk_get_rate(spi->clk),
+ A3700_SPI_MAX_PRESCALE);
+
+ a3700_spi_init(spi);
+
+ ret = devm_request_irq(dev, spi->irq, a3700_spi_interrupt, 0,
+ dev_name(dev), master);
+ if (ret) {
+ dev_err(dev, "could not request IRQ: %d\n", ret);
+ goto error_clk;
+ }
+
+ ret = devm_spi_register_master(dev, master);
+ if (ret) {
+ dev_err(dev, "Failed to register master\n");
+ goto error_clk;
+ }
+
+ return 0;
+
+error_clk:
+ clk_unprepare(spi->clk);
+error:
+ spi_master_put(master);
+out:
+ return ret;
+}
+
+static int a3700_spi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct a3700_spi *spi = spi_master_get_devdata(master);
+
+ clk_unprepare(spi->clk);
+
+ return 0;
+}
+
+static struct platform_driver a3700_spi_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = of_match_ptr(a3700_spi_dt_ids),
+ },
+ .probe = a3700_spi_probe,
+ .remove = a3700_spi_remove,
+};
+
+module_platform_driver(a3700_spi_driver);
+
+MODULE_DESCRIPTION("Armada-3700 SPI driver");
+MODULE_AUTHOR("Wilson Ding <dingwei@marvell.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME);