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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-uniphier.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-uniphier.c')
-rw-r--r--drivers/spi/spi-uniphier.c812
1 files changed, 812 insertions, 0 deletions
diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
new file mode 100644
index 000000000..cc0da4822
--- /dev/null
+++ b/drivers/spi/spi-uniphier.c
@@ -0,0 +1,812 @@
+// SPDX-License-Identifier: GPL-2.0
+// spi-uniphier.c - Socionext UniPhier SPI controller driver
+// Copyright 2012 Panasonic Corporation
+// Copyright 2016-2018 Socionext Inc.
+
+#include <linux/kernel.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+#include <asm/unaligned.h>
+
+#define SSI_TIMEOUT_MS 2000
+#define SSI_POLL_TIMEOUT_US 200
+#define SSI_MAX_CLK_DIVIDER 254
+#define SSI_MIN_CLK_DIVIDER 4
+
+struct uniphier_spi_priv {
+ void __iomem *base;
+ dma_addr_t base_dma_addr;
+ struct clk *clk;
+ struct spi_master *master;
+ struct completion xfer_done;
+
+ int error;
+ unsigned int tx_bytes;
+ unsigned int rx_bytes;
+ const u8 *tx_buf;
+ u8 *rx_buf;
+ atomic_t dma_busy;
+
+ bool is_save_param;
+ u8 bits_per_word;
+ u16 mode;
+ u32 speed_hz;
+};
+
+#define SSI_CTL 0x00
+#define SSI_CTL_EN BIT(0)
+
+#define SSI_CKS 0x04
+#define SSI_CKS_CKRAT_MASK GENMASK(7, 0)
+#define SSI_CKS_CKPHS BIT(14)
+#define SSI_CKS_CKINIT BIT(13)
+#define SSI_CKS_CKDLY BIT(12)
+
+#define SSI_TXWDS 0x08
+#define SSI_TXWDS_WDLEN_MASK GENMASK(13, 8)
+#define SSI_TXWDS_TDTF_MASK GENMASK(7, 6)
+#define SSI_TXWDS_DTLEN_MASK GENMASK(5, 0)
+
+#define SSI_RXWDS 0x0c
+#define SSI_RXWDS_DTLEN_MASK GENMASK(5, 0)
+
+#define SSI_FPS 0x10
+#define SSI_FPS_FSPOL BIT(15)
+#define SSI_FPS_FSTRT BIT(14)
+
+#define SSI_SR 0x14
+#define SSI_SR_BUSY BIT(7)
+#define SSI_SR_RNE BIT(0)
+
+#define SSI_IE 0x18
+#define SSI_IE_TCIE BIT(4)
+#define SSI_IE_RCIE BIT(3)
+#define SSI_IE_TXRE BIT(2)
+#define SSI_IE_RXRE BIT(1)
+#define SSI_IE_RORIE BIT(0)
+#define SSI_IE_ALL_MASK GENMASK(4, 0)
+
+#define SSI_IS 0x1c
+#define SSI_IS_RXRS BIT(9)
+#define SSI_IS_RCID BIT(3)
+#define SSI_IS_RORID BIT(0)
+
+#define SSI_IC 0x1c
+#define SSI_IC_TCIC BIT(4)
+#define SSI_IC_RCIC BIT(3)
+#define SSI_IC_RORIC BIT(0)
+
+#define SSI_FC 0x20
+#define SSI_FC_TXFFL BIT(12)
+#define SSI_FC_TXFTH_MASK GENMASK(11, 8)
+#define SSI_FC_RXFFL BIT(4)
+#define SSI_FC_RXFTH_MASK GENMASK(3, 0)
+
+#define SSI_TXDR 0x24
+#define SSI_RXDR 0x24
+
+#define SSI_FIFO_DEPTH 8U
+#define SSI_FIFO_BURST_NUM 1
+
+#define SSI_DMA_RX_BUSY BIT(1)
+#define SSI_DMA_TX_BUSY BIT(0)
+
+static inline unsigned int bytes_per_word(unsigned int bits)
+{
+ return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4);
+}
+
+static inline void uniphier_spi_irq_enable(struct uniphier_spi_priv *priv,
+ u32 mask)
+{
+ u32 val;
+
+ val = readl(priv->base + SSI_IE);
+ val |= mask;
+ writel(val, priv->base + SSI_IE);
+}
+
+static inline void uniphier_spi_irq_disable(struct uniphier_spi_priv *priv,
+ u32 mask)
+{
+ u32 val;
+
+ val = readl(priv->base + SSI_IE);
+ val &= ~mask;
+ writel(val, priv->base + SSI_IE);
+}
+
+static void uniphier_spi_set_mode(struct spi_device *spi)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+ u32 val1, val2;
+
+ /*
+ * clock setting
+ * CKPHS capture timing. 0:rising edge, 1:falling edge
+ * CKINIT clock initial level. 0:low, 1:high
+ * CKDLY clock delay. 0:no delay, 1:delay depending on FSTRT
+ * (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
+ *
+ * frame setting
+ * FSPOL frame signal porarity. 0: low, 1: high
+ * FSTRT start frame timing
+ * 0: rising edge of clock, 1: falling edge of clock
+ */
+ switch (spi->mode & SPI_MODE_X_MASK) {
+ case SPI_MODE_0:
+ /* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
+ val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
+ val2 = 0;
+ break;
+ case SPI_MODE_1:
+ /* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
+ val1 = 0;
+ val2 = SSI_FPS_FSTRT;
+ break;
+ case SPI_MODE_2:
+ /* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
+ val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
+ val2 = SSI_FPS_FSTRT;
+ break;
+ case SPI_MODE_3:
+ /* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
+ val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
+ val2 = 0;
+ break;
+ }
+
+ if (!(spi->mode & SPI_CS_HIGH))
+ val2 |= SSI_FPS_FSPOL;
+
+ writel(val1, priv->base + SSI_CKS);
+ writel(val2, priv->base + SSI_FPS);
+
+ val1 = 0;
+ if (spi->mode & SPI_LSB_FIRST)
+ val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
+ writel(val1, priv->base + SSI_TXWDS);
+ writel(val1, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_transfer_size(struct spi_device *spi, int size)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+ u32 val;
+
+ val = readl(priv->base + SSI_TXWDS);
+ val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
+ val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
+ val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
+ writel(val, priv->base + SSI_TXWDS);
+
+ val = readl(priv->base + SSI_RXWDS);
+ val &= ~SSI_RXWDS_DTLEN_MASK;
+ val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
+ writel(val, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_baudrate(struct spi_device *spi,
+ unsigned int speed)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+ u32 val, ckdiv;
+
+ /*
+ * the supported rates are even numbers from 4 to 254. (4,6,8...254)
+ * round up as we look for equal or less speed
+ */
+ ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
+ ckdiv = round_up(ckdiv, 2);
+
+ val = readl(priv->base + SSI_CKS);
+ val &= ~SSI_CKS_CKRAT_MASK;
+ val |= ckdiv & SSI_CKS_CKRAT_MASK;
+ writel(val, priv->base + SSI_CKS);
+}
+
+static void uniphier_spi_setup_transfer(struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+ u32 val;
+
+ priv->error = 0;
+ priv->tx_buf = t->tx_buf;
+ priv->rx_buf = t->rx_buf;
+ priv->tx_bytes = priv->rx_bytes = t->len;
+
+ if (!priv->is_save_param || priv->mode != spi->mode) {
+ uniphier_spi_set_mode(spi);
+ priv->mode = spi->mode;
+ priv->is_save_param = false;
+ }
+
+ if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
+ uniphier_spi_set_transfer_size(spi, t->bits_per_word);
+ priv->bits_per_word = t->bits_per_word;
+ }
+
+ if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
+ uniphier_spi_set_baudrate(spi, t->speed_hz);
+ priv->speed_hz = t->speed_hz;
+ }
+
+ priv->is_save_param = true;
+
+ /* reset FIFOs */
+ val = SSI_FC_TXFFL | SSI_FC_RXFFL;
+ writel(val, priv->base + SSI_FC);
+}
+
+static void uniphier_spi_send(struct uniphier_spi_priv *priv)
+{
+ int wsize;
+ u32 val = 0;
+
+ wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
+ priv->tx_bytes -= wsize;
+
+ if (priv->tx_buf) {
+ switch (wsize) {
+ case 1:
+ val = *priv->tx_buf;
+ break;
+ case 2:
+ val = get_unaligned_le16(priv->tx_buf);
+ break;
+ case 4:
+ val = get_unaligned_le32(priv->tx_buf);
+ break;
+ }
+
+ priv->tx_buf += wsize;
+ }
+
+ writel(val, priv->base + SSI_TXDR);
+}
+
+static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
+{
+ int rsize;
+ u32 val;
+
+ rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
+ priv->rx_bytes -= rsize;
+
+ val = readl(priv->base + SSI_RXDR);
+
+ if (priv->rx_buf) {
+ switch (rsize) {
+ case 1:
+ *priv->rx_buf = val;
+ break;
+ case 2:
+ put_unaligned_le16(val, priv->rx_buf);
+ break;
+ case 4:
+ put_unaligned_le32(val, priv->rx_buf);
+ break;
+ }
+
+ priv->rx_buf += rsize;
+ }
+}
+
+static void uniphier_spi_set_fifo_threshold(struct uniphier_spi_priv *priv,
+ unsigned int threshold)
+{
+ u32 val;
+
+ val = readl(priv->base + SSI_FC);
+ val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
+ val |= FIELD_PREP(SSI_FC_TXFTH_MASK, SSI_FIFO_DEPTH - threshold);
+ val |= FIELD_PREP(SSI_FC_RXFTH_MASK, threshold);
+ writel(val, priv->base + SSI_FC);
+}
+
+static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
+{
+ unsigned int fifo_threshold, fill_words;
+ unsigned int bpw = bytes_per_word(priv->bits_per_word);
+
+ fifo_threshold = DIV_ROUND_UP(priv->rx_bytes, bpw);
+ fifo_threshold = min(fifo_threshold, SSI_FIFO_DEPTH);
+
+ uniphier_spi_set_fifo_threshold(priv, fifo_threshold);
+
+ fill_words = fifo_threshold -
+ DIV_ROUND_UP(priv->rx_bytes - priv->tx_bytes, bpw);
+
+ while (fill_words--)
+ uniphier_spi_send(priv);
+}
+
+static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+ u32 val;
+
+ val = readl(priv->base + SSI_FPS);
+
+ if (enable)
+ val |= SSI_FPS_FSPOL;
+ else
+ val &= ~SSI_FPS_FSPOL;
+
+ writel(val, priv->base + SSI_FPS);
+}
+
+static bool uniphier_spi_can_dma(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+ unsigned int bpw = bytes_per_word(priv->bits_per_word);
+
+ if ((!master->dma_tx && !master->dma_rx)
+ || (!master->dma_tx && t->tx_buf)
+ || (!master->dma_rx && t->rx_buf))
+ return false;
+
+ return DIV_ROUND_UP(t->len, bpw) > SSI_FIFO_DEPTH;
+}
+
+static void uniphier_spi_dma_rxcb(void *data)
+{
+ struct spi_master *master = data;
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+ int state = atomic_fetch_andnot(SSI_DMA_RX_BUSY, &priv->dma_busy);
+
+ uniphier_spi_irq_disable(priv, SSI_IE_RXRE);
+
+ if (!(state & SSI_DMA_TX_BUSY))
+ spi_finalize_current_transfer(master);
+}
+
+static void uniphier_spi_dma_txcb(void *data)
+{
+ struct spi_master *master = data;
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+ int state = atomic_fetch_andnot(SSI_DMA_TX_BUSY, &priv->dma_busy);
+
+ uniphier_spi_irq_disable(priv, SSI_IE_TXRE);
+
+ if (!(state & SSI_DMA_RX_BUSY))
+ spi_finalize_current_transfer(master);
+}
+
+static int uniphier_spi_transfer_one_dma(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+ struct dma_async_tx_descriptor *rxdesc = NULL, *txdesc = NULL;
+ int buswidth;
+
+ atomic_set(&priv->dma_busy, 0);
+
+ uniphier_spi_set_fifo_threshold(priv, SSI_FIFO_BURST_NUM);
+
+ if (priv->bits_per_word <= 8)
+ buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ else if (priv->bits_per_word <= 16)
+ buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ else
+ buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
+
+ if (priv->rx_buf) {
+ struct dma_slave_config rxconf = {
+ .direction = DMA_DEV_TO_MEM,
+ .src_addr = priv->base_dma_addr + SSI_RXDR,
+ .src_addr_width = buswidth,
+ .src_maxburst = SSI_FIFO_BURST_NUM,
+ };
+
+ dmaengine_slave_config(master->dma_rx, &rxconf);
+
+ rxdesc = dmaengine_prep_slave_sg(
+ master->dma_rx,
+ t->rx_sg.sgl, t->rx_sg.nents,
+ DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!rxdesc)
+ goto out_err_prep;
+
+ rxdesc->callback = uniphier_spi_dma_rxcb;
+ rxdesc->callback_param = master;
+
+ uniphier_spi_irq_enable(priv, SSI_IE_RXRE);
+ atomic_or(SSI_DMA_RX_BUSY, &priv->dma_busy);
+
+ dmaengine_submit(rxdesc);
+ dma_async_issue_pending(master->dma_rx);
+ }
+
+ if (priv->tx_buf) {
+ struct dma_slave_config txconf = {
+ .direction = DMA_MEM_TO_DEV,
+ .dst_addr = priv->base_dma_addr + SSI_TXDR,
+ .dst_addr_width = buswidth,
+ .dst_maxburst = SSI_FIFO_BURST_NUM,
+ };
+
+ dmaengine_slave_config(master->dma_tx, &txconf);
+
+ txdesc = dmaengine_prep_slave_sg(
+ master->dma_tx,
+ t->tx_sg.sgl, t->tx_sg.nents,
+ DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!txdesc)
+ goto out_err_prep;
+
+ txdesc->callback = uniphier_spi_dma_txcb;
+ txdesc->callback_param = master;
+
+ uniphier_spi_irq_enable(priv, SSI_IE_TXRE);
+ atomic_or(SSI_DMA_TX_BUSY, &priv->dma_busy);
+
+ dmaengine_submit(txdesc);
+ dma_async_issue_pending(master->dma_tx);
+ }
+
+ /* signal that we need to wait for completion */
+ return (priv->tx_buf || priv->rx_buf);
+
+out_err_prep:
+ if (rxdesc)
+ dmaengine_terminate_sync(master->dma_rx);
+
+ return -EINVAL;
+}
+
+static int uniphier_spi_transfer_one_irq(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+ struct device *dev = master->dev.parent;
+ unsigned long time_left;
+
+ reinit_completion(&priv->xfer_done);
+
+ uniphier_spi_fill_tx_fifo(priv);
+
+ uniphier_spi_irq_enable(priv, SSI_IE_RCIE | SSI_IE_RORIE);
+
+ time_left = wait_for_completion_timeout(&priv->xfer_done,
+ msecs_to_jiffies(SSI_TIMEOUT_MS));
+
+ uniphier_spi_irq_disable(priv, SSI_IE_RCIE | SSI_IE_RORIE);
+
+ if (!time_left) {
+ dev_err(dev, "transfer timeout.\n");
+ return -ETIMEDOUT;
+ }
+
+ return priv->error;
+}
+
+static int uniphier_spi_transfer_one_poll(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+ int loop = SSI_POLL_TIMEOUT_US * 10;
+
+ while (priv->tx_bytes) {
+ uniphier_spi_fill_tx_fifo(priv);
+
+ while ((priv->rx_bytes - priv->tx_bytes) > 0) {
+ while (!(readl(priv->base + SSI_SR) & SSI_SR_RNE)
+ && loop--)
+ ndelay(100);
+
+ if (loop == -1)
+ goto irq_transfer;
+
+ uniphier_spi_recv(priv);
+ }
+ }
+
+ return 0;
+
+irq_transfer:
+ return uniphier_spi_transfer_one_irq(master, spi, t);
+}
+
+static int uniphier_spi_transfer_one(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+ unsigned long threshold;
+ bool use_dma;
+
+ /* Terminate and return success for 0 byte length transfer */
+ if (!t->len)
+ return 0;
+
+ uniphier_spi_setup_transfer(spi, t);
+
+ use_dma = master->can_dma ? master->can_dma(master, spi, t) : false;
+ if (use_dma)
+ return uniphier_spi_transfer_one_dma(master, spi, t);
+
+ /*
+ * If the transfer operation will take longer than
+ * SSI_POLL_TIMEOUT_US, it should use irq.
+ */
+ threshold = DIV_ROUND_UP(SSI_POLL_TIMEOUT_US * priv->speed_hz,
+ USEC_PER_SEC * BITS_PER_BYTE);
+ if (t->len > threshold)
+ return uniphier_spi_transfer_one_irq(master, spi, t);
+ else
+ return uniphier_spi_transfer_one_poll(master, spi, t);
+}
+
+static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+ writel(SSI_CTL_EN, priv->base + SSI_CTL);
+
+ return 0;
+}
+
+static int uniphier_spi_unprepare_transfer_hardware(struct spi_master *master)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+ writel(0, priv->base + SSI_CTL);
+
+ return 0;
+}
+
+static void uniphier_spi_handle_err(struct spi_master *master,
+ struct spi_message *msg)
+{
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+ u32 val;
+
+ /* stop running spi transfer */
+ writel(0, priv->base + SSI_CTL);
+
+ /* reset FIFOs */
+ val = SSI_FC_TXFFL | SSI_FC_RXFFL;
+ writel(val, priv->base + SSI_FC);
+
+ uniphier_spi_irq_disable(priv, SSI_IE_ALL_MASK);
+
+ if (atomic_read(&priv->dma_busy) & SSI_DMA_TX_BUSY) {
+ dmaengine_terminate_async(master->dma_tx);
+ atomic_andnot(SSI_DMA_TX_BUSY, &priv->dma_busy);
+ }
+
+ if (atomic_read(&priv->dma_busy) & SSI_DMA_RX_BUSY) {
+ dmaengine_terminate_async(master->dma_rx);
+ atomic_andnot(SSI_DMA_RX_BUSY, &priv->dma_busy);
+ }
+}
+
+static irqreturn_t uniphier_spi_handler(int irq, void *dev_id)
+{
+ struct uniphier_spi_priv *priv = dev_id;
+ u32 val, stat;
+
+ stat = readl(priv->base + SSI_IS);
+ val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
+ writel(val, priv->base + SSI_IC);
+
+ /* rx fifo overrun */
+ if (stat & SSI_IS_RORID) {
+ priv->error = -EIO;
+ goto done;
+ }
+
+ /* rx complete */
+ if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
+ while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
+ (priv->rx_bytes - priv->tx_bytes) > 0)
+ uniphier_spi_recv(priv);
+
+ if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
+ (priv->rx_bytes != priv->tx_bytes)) {
+ priv->error = -EIO;
+ goto done;
+ } else if (priv->rx_bytes == 0)
+ goto done;
+
+ /* next tx transfer */
+ uniphier_spi_fill_tx_fifo(priv);
+
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+
+done:
+ complete(&priv->xfer_done);
+ return IRQ_HANDLED;
+}
+
+static int uniphier_spi_probe(struct platform_device *pdev)
+{
+ struct uniphier_spi_priv *priv;
+ struct spi_master *master;
+ struct resource *res;
+ struct dma_slave_caps caps;
+ u32 dma_tx_burst = 0, dma_rx_burst = 0;
+ unsigned long clk_rate;
+ int irq;
+ int ret;
+
+ master = spi_alloc_master(&pdev->dev, sizeof(*priv));
+ if (!master)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, master);
+
+ priv = spi_master_get_devdata(master);
+ priv->master = master;
+ priv->is_save_param = false;
+
+ priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+ if (IS_ERR(priv->base)) {
+ ret = PTR_ERR(priv->base);
+ goto out_master_put;
+ }
+ priv->base_dma_addr = res->start;
+
+ priv->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(priv->clk)) {
+ dev_err(&pdev->dev, "failed to get clock\n");
+ ret = PTR_ERR(priv->clk);
+ goto out_master_put;
+ }
+
+ ret = clk_prepare_enable(priv->clk);
+ if (ret)
+ goto out_master_put;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ ret = irq;
+ goto out_disable_clk;
+ }
+
+ ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
+ 0, "uniphier-spi", priv);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request IRQ\n");
+ goto out_disable_clk;
+ }
+
+ init_completion(&priv->xfer_done);
+
+ clk_rate = clk_get_rate(priv->clk);
+
+ master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
+ master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
+ master->dev.of_node = pdev->dev.of_node;
+ master->bus_num = pdev->id;
+ master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
+
+ master->set_cs = uniphier_spi_set_cs;
+ master->transfer_one = uniphier_spi_transfer_one;
+ master->prepare_transfer_hardware
+ = uniphier_spi_prepare_transfer_hardware;
+ master->unprepare_transfer_hardware
+ = uniphier_spi_unprepare_transfer_hardware;
+ master->handle_err = uniphier_spi_handle_err;
+ master->can_dma = uniphier_spi_can_dma;
+
+ master->num_chipselect = 1;
+ master->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
+
+ master->dma_tx = dma_request_chan(&pdev->dev, "tx");
+ if (IS_ERR_OR_NULL(master->dma_tx)) {
+ if (PTR_ERR(master->dma_tx) == -EPROBE_DEFER) {
+ ret = -EPROBE_DEFER;
+ goto out_disable_clk;
+ }
+ master->dma_tx = NULL;
+ dma_tx_burst = INT_MAX;
+ } else {
+ ret = dma_get_slave_caps(master->dma_tx, &caps);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to get TX DMA capacities: %d\n",
+ ret);
+ goto out_release_dma;
+ }
+ dma_tx_burst = caps.max_burst;
+ }
+
+ master->dma_rx = dma_request_chan(&pdev->dev, "rx");
+ if (IS_ERR_OR_NULL(master->dma_rx)) {
+ if (PTR_ERR(master->dma_rx) == -EPROBE_DEFER) {
+ ret = -EPROBE_DEFER;
+ goto out_release_dma;
+ }
+ master->dma_rx = NULL;
+ dma_rx_burst = INT_MAX;
+ } else {
+ ret = dma_get_slave_caps(master->dma_rx, &caps);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to get RX DMA capacities: %d\n",
+ ret);
+ goto out_release_dma;
+ }
+ dma_rx_burst = caps.max_burst;
+ }
+
+ master->max_dma_len = min(dma_tx_burst, dma_rx_burst);
+
+ ret = devm_spi_register_master(&pdev->dev, master);
+ if (ret)
+ goto out_release_dma;
+
+ return 0;
+
+out_release_dma:
+ if (!IS_ERR_OR_NULL(master->dma_rx)) {
+ dma_release_channel(master->dma_rx);
+ master->dma_rx = NULL;
+ }
+ if (!IS_ERR_OR_NULL(master->dma_tx)) {
+ dma_release_channel(master->dma_tx);
+ master->dma_tx = NULL;
+ }
+
+out_disable_clk:
+ clk_disable_unprepare(priv->clk);
+
+out_master_put:
+ spi_master_put(master);
+ return ret;
+}
+
+static int uniphier_spi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+ if (master->dma_tx)
+ dma_release_channel(master->dma_tx);
+ if (master->dma_rx)
+ dma_release_channel(master->dma_rx);
+
+ clk_disable_unprepare(priv->clk);
+
+ return 0;
+}
+
+static const struct of_device_id uniphier_spi_match[] = {
+ { .compatible = "socionext,uniphier-scssi" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_spi_match);
+
+static struct platform_driver uniphier_spi_driver = {
+ .probe = uniphier_spi_probe,
+ .remove = uniphier_spi_remove,
+ .driver = {
+ .name = "uniphier-spi",
+ .of_match_table = uniphier_spi_match,
+ },
+};
+module_platform_driver(uniphier_spi_driver);
+
+MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
+MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
+MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
+MODULE_LICENSE("GPL v2");