--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2017 Hisilicon Limited, All Rights Reserved.
+ * Author: Zhichang Yuan <yuanzhichang@hisilicon.com>
+ * Author: Zou Rongrong <zourongrong@huawei.com>
+ * Author: John Garry <john.garry@huawei.com>
+ */
+
+#include <linux/acpi.h>
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/logic_pio.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+
+#define DRV_NAME "hisi-lpc"
+
+/*
+ * Setting this bit means each IO operation will target a different port
+ * address; 0 means repeated IO operations will use the same port,
+ * such as BT.
+ */
+#define FG_INCRADDR_LPC 0x02
+
+struct lpc_cycle_para {
+ unsigned int opflags;
+ unsigned int csize; /* data length of each operation */
+};
+
+struct hisi_lpc_dev {
+ spinlock_t cycle_lock;
+ void __iomem *membase;
+ struct logic_pio_hwaddr *io_host;
+};
+
+/* The max IO cycle counts supported is four per operation at maximum */
+#define LPC_MAX_DWIDTH 4
+
+#define LPC_REG_STARTUP_SIGNAL 0x00
+#define LPC_REG_STARTUP_SIGNAL_START BIT(0)
+#define LPC_REG_OP_STATUS 0x04
+#define LPC_REG_OP_STATUS_IDLE BIT(0)
+#define LPC_REG_OP_STATUS_FINISHED BIT(1)
+#define LPC_REG_OP_LEN 0x10 /* LPC cycles count per start */
+#define LPC_REG_CMD 0x14
+#define LPC_REG_CMD_OP BIT(0) /* 0: read, 1: write */
+#define LPC_REG_CMD_SAMEADDR BIT(3)
+#define LPC_REG_ADDR 0x20 /* target address */
+#define LPC_REG_WDATA 0x24 /* write FIFO */
+#define LPC_REG_RDATA 0x28 /* read FIFO */
+
+/* The minimal nanosecond interval for each query on LPC cycle status */
+#define LPC_NSEC_PERWAIT 100
+
+/*
+ * The maximum waiting time is about 128us. It is specific for stream I/O,
+ * such as ins.
+ *
+ * The fastest IO cycle time is about 390ns, but the worst case will wait
+ * for extra 256 lpc clocks, so (256 + 13) * 30ns = 8 us. The maximum burst
+ * cycles is 16. So, the maximum waiting time is about 128us under worst
+ * case.
+ *
+ * Choose 1300 as the maximum.
+ */
+#define LPC_MAX_WAITCNT 1300
+
+/* About 10us. This is specific for single IO operations, such as inb */
+#define LPC_PEROP_WAITCNT 100
+
+static int wait_lpc_idle(unsigned char *mbase, unsigned int waitcnt)
+{
+ u32 status;
+
+ do {
+ status = readl(mbase + LPC_REG_OP_STATUS);
+ if (status & LPC_REG_OP_STATUS_IDLE)
+ return (status & LPC_REG_OP_STATUS_FINISHED) ? 0 : -EIO;
+ ndelay(LPC_NSEC_PERWAIT);
+ } while (--waitcnt);
+
+ return -ETIME;
+}
+
+/*
+ * hisi_lpc_target_in - trigger a series of LPC cycles for read operation
+ * @lpcdev: pointer to hisi lpc device
+ * @para: some parameters used to control the lpc I/O operations
+ * @addr: the lpc I/O target port address
+ * @buf: where the read back data is stored
+ * @opcnt: how many I/O operations required, i.e. data width
+ *
+ * Returns 0 on success, non-zero on fail.
+ */
+static int hisi_lpc_target_in(struct hisi_lpc_dev *lpcdev,
+ struct lpc_cycle_para *para, unsigned long addr,
+ unsigned char *buf, unsigned long opcnt)
+{
+ unsigned int cmd_word;
+ unsigned int waitcnt;
+ unsigned long flags;
+ int ret;
+
+ if (!buf || !opcnt || !para || !para->csize || !lpcdev)
+ return -EINVAL;
+
+ cmd_word = 0; /* IO mode, Read */
+ waitcnt = LPC_PEROP_WAITCNT;
+ if (!(para->opflags & FG_INCRADDR_LPC)) {
+ cmd_word |= LPC_REG_CMD_SAMEADDR;
+ waitcnt = LPC_MAX_WAITCNT;
+ }
+
+ /* whole operation must be atomic */
+ spin_lock_irqsave(&lpcdev->cycle_lock, flags);
+
+ writel_relaxed(opcnt, lpcdev->membase + LPC_REG_OP_LEN);
+ writel_relaxed(cmd_word, lpcdev->membase + LPC_REG_CMD);
+ writel_relaxed(addr, lpcdev->membase + LPC_REG_ADDR);
+
+ writel(LPC_REG_STARTUP_SIGNAL_START,
+ lpcdev->membase + LPC_REG_STARTUP_SIGNAL);
+
+ /* whether the operation is finished */
+ ret = wait_lpc_idle(lpcdev->membase, waitcnt);
+ if (ret) {
+ spin_unlock_irqrestore(&lpcdev->cycle_lock, flags);
+ return ret;
+ }
+
+ readsb(lpcdev->membase + LPC_REG_RDATA, buf, opcnt);
+
+ spin_unlock_irqrestore(&lpcdev->cycle_lock, flags);
+
+ return 0;
+}
+
+/*
+ * hisi_lpc_target_out - trigger a series of LPC cycles for write operation
+ * @lpcdev: pointer to hisi lpc device
+ * @para: some parameters used to control the lpc I/O operations
+ * @addr: the lpc I/O target port address
+ * @buf: where the data to be written is stored
+ * @opcnt: how many I/O operations required, i.e. data width
+ *
+ * Returns 0 on success, non-zero on fail.
+ */
+static int hisi_lpc_target_out(struct hisi_lpc_dev *lpcdev,
+ struct lpc_cycle_para *para, unsigned long addr,
+ const unsigned char *buf, unsigned long opcnt)
+{
+ unsigned int waitcnt;
+ unsigned long flags;
+ u32 cmd_word;
+ int ret;
+
+ if (!buf || !opcnt || !para || !lpcdev)
+ return -EINVAL;
+
+ /* default is increasing address */
+ cmd_word = LPC_REG_CMD_OP; /* IO mode, write */
+ waitcnt = LPC_PEROP_WAITCNT;
+ if (!(para->opflags & FG_INCRADDR_LPC)) {
+ cmd_word |= LPC_REG_CMD_SAMEADDR;
+ waitcnt = LPC_MAX_WAITCNT;
+ }
+
+ spin_lock_irqsave(&lpcdev->cycle_lock, flags);
+
+ writel_relaxed(opcnt, lpcdev->membase + LPC_REG_OP_LEN);
+ writel_relaxed(cmd_word, lpcdev->membase + LPC_REG_CMD);
+ writel_relaxed(addr, lpcdev->membase + LPC_REG_ADDR);
+
+ writesb(lpcdev->membase + LPC_REG_WDATA, buf, opcnt);
+
+ writel(LPC_REG_STARTUP_SIGNAL_START,
+ lpcdev->membase + LPC_REG_STARTUP_SIGNAL);
+
+ /* whether the operation is finished */
+ ret = wait_lpc_idle(lpcdev->membase, waitcnt);
+
+ spin_unlock_irqrestore(&lpcdev->cycle_lock, flags);
+
+ return ret;
+}
+
+static unsigned long hisi_lpc_pio_to_addr(struct hisi_lpc_dev *lpcdev,
+ unsigned long pio)
+{
+ return pio - lpcdev->io_host->io_start + lpcdev->io_host->hw_start;
+}
+
+/*
+ * hisi_lpc_comm_in - input the data in a single operation
+ * @hostdata: pointer to the device information relevant to LPC controller
+ * @pio: the target I/O port address
+ * @dwidth: the data length required to read from the target I/O port
+ *
+ * When success, data is returned. Otherwise, ~0 is returned.
+ */
+static u32 hisi_lpc_comm_in(void *hostdata, unsigned long pio, size_t dwidth)
+{
+ struct hisi_lpc_dev *lpcdev = hostdata;
+ struct lpc_cycle_para iopara;
+ unsigned long addr;
+ u32 rd_data = 0;
+ int ret;
+
+ if (!lpcdev || !dwidth || dwidth > LPC_MAX_DWIDTH)
+ return ~0;
+
+ addr = hisi_lpc_pio_to_addr(lpcdev, pio);
+
+ iopara.opflags = FG_INCRADDR_LPC;
+ iopara.csize = dwidth;
+
+ ret = hisi_lpc_target_in(lpcdev, &iopara, addr,
+ (unsigned char *)&rd_data, dwidth);
+ if (ret)
+ return ~0;
+
+ return le32_to_cpu(rd_data);
+}
+
+/*
+ * hisi_lpc_comm_out - output the data in a single operation
+ * @hostdata: pointer to the device information relevant to LPC controller
+ * @pio: the target I/O port address
+ * @val: a value to be output from caller, maximum is four bytes
+ * @dwidth: the data width required writing to the target I/O port
+ *
+ * This function corresponds to out(b,w,l) only.
+ */
+static void hisi_lpc_comm_out(void *hostdata, unsigned long pio,
+ u32 val, size_t dwidth)
+{
+ struct hisi_lpc_dev *lpcdev = hostdata;
+ struct lpc_cycle_para iopara;
+ const unsigned char *buf;
+ unsigned long addr;
+
+ if (!lpcdev || !dwidth || dwidth > LPC_MAX_DWIDTH)
+ return;
+
+ val = cpu_to_le32(val);
+
+ buf = (const unsigned char *)&val;
+ addr = hisi_lpc_pio_to_addr(lpcdev, pio);
+
+ iopara.opflags = FG_INCRADDR_LPC;
+ iopara.csize = dwidth;
+
+ hisi_lpc_target_out(lpcdev, &iopara, addr, buf, dwidth);
+}
+
+/*
+ * hisi_lpc_comm_ins - input the data in the buffer in multiple operations
+ * @hostdata: pointer to the device information relevant to LPC controller
+ * @pio: the target I/O port address
+ * @buffer: a buffer where read/input data bytes are stored
+ * @dwidth: the data width required writing to the target I/O port
+ * @count: how many data units whose length is dwidth will be read
+ *
+ * When success, the data read back is stored in buffer pointed by buffer.
+ * Returns 0 on success, -errno otherwise.
+ */
+static u32 hisi_lpc_comm_ins(void *hostdata, unsigned long pio, void *buffer,
+ size_t dwidth, unsigned int count)
+{
+ struct hisi_lpc_dev *lpcdev = hostdata;
+ unsigned char *buf = buffer;
+ struct lpc_cycle_para iopara;
+ unsigned long addr;
+
+ if (!lpcdev || !buf || !count || !dwidth || dwidth > LPC_MAX_DWIDTH)
+ return -EINVAL;
+
+ iopara.opflags = 0;
+ if (dwidth > 1)
+ iopara.opflags |= FG_INCRADDR_LPC;
+ iopara.csize = dwidth;
+
+ addr = hisi_lpc_pio_to_addr(lpcdev, pio);
+
+ do {
+ int ret;
+
+ ret = hisi_lpc_target_in(lpcdev, &iopara, addr, buf, dwidth);
+ if (ret)
+ return ret;
+ buf += dwidth;
+ } while (--count);
+
+ return 0;
+}
+
+/*
+ * hisi_lpc_comm_outs - output the data in the buffer in multiple operations
+ * @hostdata: pointer to the device information relevant to LPC controller
+ * @pio: the target I/O port address
+ * @buffer: a buffer where write/output data bytes are stored
+ * @dwidth: the data width required writing to the target I/O port
+ * @count: how many data units whose length is dwidth will be written
+ */
+static void hisi_lpc_comm_outs(void *hostdata, unsigned long pio,
+ const void *buffer, size_t dwidth,
+ unsigned int count)
+{
+ struct hisi_lpc_dev *lpcdev = hostdata;
+ struct lpc_cycle_para iopara;
+ const unsigned char *buf = buffer;
+ unsigned long addr;
+
+ if (!lpcdev || !buf || !count || !dwidth || dwidth > LPC_MAX_DWIDTH)
+ return;
+
+ iopara.opflags = 0;
+ if (dwidth > 1)
+ iopara.opflags |= FG_INCRADDR_LPC;
+ iopara.csize = dwidth;
+
+ addr = hisi_lpc_pio_to_addr(lpcdev, pio);
+ do {
+ if (hisi_lpc_target_out(lpcdev, &iopara, addr, buf, dwidth))
+ break;
+ buf += dwidth;
+ } while (--count);
+}
+
+static const struct logic_pio_host_ops hisi_lpc_ops = {
+ .in = hisi_lpc_comm_in,
+ .out = hisi_lpc_comm_out,
+ .ins = hisi_lpc_comm_ins,
+ .outs = hisi_lpc_comm_outs,
+};
+
+/*
+ * hisi_lpc_probe - the probe callback function for hisi lpc host,
+ * will finish all the initialization.
+ * @pdev: the platform device corresponding to hisi lpc host
+ *
+ * Returns 0 on success, non-zero on fail.
+ */
+static int hisi_lpc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct acpi_device *acpi_device = ACPI_COMPANION(dev);
+ struct logic_pio_hwaddr *range;
+ struct hisi_lpc_dev *lpcdev;
+ resource_size_t io_end;
+ struct resource *res;
+ int ret;
+
+ lpcdev = devm_kzalloc(dev, sizeof(*lpcdev), GFP_KERNEL);
+ if (!lpcdev)
+ return -ENOMEM;
+
+ spin_lock_init(&lpcdev->cycle_lock);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ lpcdev->membase = devm_ioremap_resource(dev, res);
+ if (IS_ERR(lpcdev->membase))
+ return PTR_ERR(lpcdev->membase);
+
+ range = devm_kzalloc(dev, sizeof(*range), GFP_KERNEL);
+ if (!range)
+ return -ENOMEM;
+
+ range->fwnode = dev->fwnode;
+ range->flags = LOGIC_PIO_INDIRECT;
+ range->size = PIO_INDIRECT_SIZE;
+
+ ret = logic_pio_register_range(range);
+ if (ret) {
+ dev_err(dev, "register IO range failed (%d)!\n", ret);
+ return ret;
+ }
+ lpcdev->io_host = range;
+
+ /* register the LPC host PIO resources */
+ if (!acpi_device) {
+ ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
+ if (ret)
+ return ret;
+ }
+
+ lpcdev->io_host->hostdata = lpcdev;
+ lpcdev->io_host->ops = &hisi_lpc_ops;
+
+ io_end = lpcdev->io_host->io_start + lpcdev->io_host->size;
+ dev_info(dev, "registered range [%pa - %pa]\n",
+ &lpcdev->io_host->io_start, &io_end);
+
+ return ret;
+}
+
+static const struct of_device_id hisi_lpc_of_match[] = {
+ { .compatible = "hisilicon,hip06-lpc", },
+ { .compatible = "hisilicon,hip07-lpc", },
+ {}
+};
+
+static struct platform_driver hisi_lpc_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = hisi_lpc_of_match,
+ },
+ .probe = hisi_lpc_probe,
+};
+builtin_platform_driver(hisi_lpc_driver);
projects / linux-2.6-microblaze.git / commitdiff