Commit adf38bb0 authored by Zhichang Yuan's avatar Zhichang Yuan Committed by Bjorn Helgaas

HISI LPC: Support the LPC host on Hip06/Hip07 with DT bindings

The low-pin-count (LPC) interface of Hip06/Hip07 accesses I/O port space of
peripherals.

Implement the LPC host controller driver which performs the I/O operations
on the underlying hardware.  We don't want to touch existing drivers such
as ipmi-bt, so this driver applies the indirect-IO introduced in the
previous patch after registering an indirect-IO node to the indirect-IO
devices list which will be searched by the I/O accessors to retrieve the
host-local I/O port.

The driver config is set as a bool instead of a tristate.  The reason here
is that, by the very nature of the driver providing a logical PIO range, it
does not make sense to have this driver as a loadable module.  Another more
specific reason is that the Huawei D03 board which includes Hip06 SoC
requires the LPC bus for UART console, so should be built in.
Tested-by: default avatardann frazier <dann.frazier@canonical.com>
Signed-off-by: default avatarZou Rongrong <zourongrong@huawei.com>
Signed-off-by: default avatarZhichang Yuan <yuanzhichang@hisilicon.com>
Signed-off-by: default avatarJohn Garry <john.garry@huawei.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>	# dts part
parent 65af618d
Hisilicon Hip06 Low Pin Count device
Hisilicon Hip06 SoCs implement a Low Pin Count (LPC) controller, which
provides I/O access to some legacy ISA devices.
Hip06 is based on arm64 architecture where there is no I/O space. So, the
I/O ports here are not CPU addresses, and there is no 'ranges' property in
LPC device node.
Required properties:
- compatible: value should be as follows:
(a) "hisilicon,hip06-lpc"
(b) "hisilicon,hip07-lpc"
- #address-cells: must be 2 which stick to the ISA/EISA binding doc.
- #size-cells: must be 1 which stick to the ISA/EISA binding doc.
- reg: base memory range where the LPC register set is mapped.
Note:
The node name before '@' must be "isa" to represent the binding stick to the
ISA/EISA binding specification.
Example:
isa@a01b0000 {
compatible = "hisilicon,hip06-lpc";
#address-cells = <2>;
#size-cells = <1>;
reg = <0x0 0xa01b0000 0x0 0x1000>;
ipmi0: bt@e4 {
compatible = "ipmi-bt";
device_type = "ipmi";
reg = <0x01 0xe4 0x04>;
};
};
......@@ -65,6 +65,14 @@ config BRCMSTB_GISB_ARB
arbiter. This driver provides timeout and target abort error handling
and internal bus master decoding.
config HISILICON_LPC
bool "Support for ISA I/O space on HiSilicon Hip06/7"
depends on ARM64 && (ARCH_HISI || COMPILE_TEST)
select INDIRECT_PIO
help
Driver to enable I/O access to devices attached to the Low Pin
Count bus on the HiSilicon Hip06/7 SoC.
config IMX_WEIM
bool "Freescale EIM DRIVER"
depends on ARCH_MXC
......
......@@ -7,6 +7,7 @@
obj-$(CONFIG_ARM_CCI) += arm-cci.o
obj-$(CONFIG_ARM_CCN) += arm-ccn.o
obj-$(CONFIG_HISILICON_LPC) += hisi_lpc.o
obj-$(CONFIG_BRCMSTB_GISB_ARB) += brcmstb_gisb.o
obj-$(CONFIG_IMX_WEIM) += imx-weim.o
obj-$(CONFIG_MIPS_CDMM) += mips_cdmm.o
......
// 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);
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