From 102635b19ac5df2ed785e64e519615c4109cf76f Mon Sep 17 00:00:00 2001 From: liyuting Date: Tue, 14 May 2024 15:19:29 +0800 Subject: [PATCH] ipmi: Add Phytium BT BMC driver support This patch adds a simple device driver to expose the BT interface on Phytium SoC as a character device. Such SOCs are commonly used as BMCs (BaseBoard Management Controllers) and this driver implements the BMC side of the BT interface. Signed-off-by: Li Yuting Signed-off-by: Cheng Quan Signed-off-by: Chen Zhenhua Signed-off-by: Chen Baozi Signed-off-by: Wang Yinfeng --- drivers/char/ipmi/Kconfig | 9 + drivers/char/ipmi/Makefile | 1 + drivers/char/ipmi/bt_bmc_phytium.c | 533 +++++++++++++++++++++++++++++ 3 files changed, 543 insertions(+) create mode 100644 drivers/char/ipmi/bt_bmc_phytium.c diff --git a/drivers/char/ipmi/Kconfig b/drivers/char/ipmi/Kconfig index 63c83c2f181ec..0902475affd27 100644 --- a/drivers/char/ipmi/Kconfig +++ b/drivers/char/ipmi/Kconfig @@ -130,6 +130,15 @@ config PHYTIUM_KCS_IPMI_BMC The driver implements the BMC side of the KCS contorller, it provides the access of KCS IO space for BMC side. +config PHYTIUM_BT_IPMI_BMC + depends on ARCH_PHYTIUM + depends on REGMAP && REGMAP_MMIO && MFD_SYSCON + tristate "PHYTIUM BT BMC driver" + help + Provides a driver for the BT (Block Transfer) interface found + on Phytium SOCs. The driver implements the BMC side of + the BT interface. + config NPCM7XX_KCS_IPMI_BMC depends on ARCH_NPCM || COMPILE_TEST select IPMI_KCS_BMC diff --git a/drivers/char/ipmi/Makefile b/drivers/char/ipmi/Makefile index 7b806f9a08be7..e0f2d90e151b3 100644 --- a/drivers/char/ipmi/Makefile +++ b/drivers/char/ipmi/Makefile @@ -32,3 +32,4 @@ obj-$(CONFIG_NPCM7XX_KCS_IPMI_BMC) += kcs_bmc_npcm7xx.o obj-$(CONFIG_IPMB_DEVICE_INTERFACE) += ipmb_dev_int.o obj-$(CONFIG_SSIF_IPMI_BMC) += ssif_bmc.o obj-$(CONFIG_PHYTIUM_KCS_IPMI_BMC) += kcs_bmc_phytium.o +obj-$(CONFIG_PHYTIUM_BT_IPMI_BMC) += bt_bmc_phytium.o diff --git a/drivers/char/ipmi/bt_bmc_phytium.c b/drivers/char/ipmi/bt_bmc_phytium.c new file mode 100644 index 0000000000000..7777e7a6bb995 --- /dev/null +++ b/drivers/char/ipmi/bt_bmc_phytium.c @@ -0,0 +1,533 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2021-2023, Phytium Technology, Co., Ltd. + * + * Derived from drivers/char/ipmi/bt-bmc.c + * Copyright (c) 2015-2016, IBM Corporation. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * This is a BMC device used to communicate to the host + */ +#define DEVICE_NAME "ipmi-bt-host" + +#define BT_IO_BASE 0xe4 +#define BT_IRQ 10 + +#define LPC_HICR0 0x00 +#define LPC_HICR0_LPC3E BIT(7) +#define LPC_HICR0_LPC2E BIT(6) +#define LPC_HICR0_LPC1E BIT(5) +#define LPC_HICR0_SDWNE BIT(3) /* 0:disabl,1:enable for HICR1_SDWNB */ +#define LPC_HICR0_PMEE BIT(2) /* 0:disabl,1:enable for HICR1_PMEB */ + +#define LPC_HICR2 0x08 +#define LPC_HICR2_IBFIF3 BIT(3) /* 0:normal,1:enable irq 3*/ + +#define LPC_HICR4 0x10 +#define LPC_HICR4_LADR12AS BIT(7) +#define LPC_HICR4_KCSENBL BIT(2) +#define LPC_BTENABLE BIT(0) /* share bt channel enable,0:disable,1:enable */ +#define LPC_LADR3H_BT 0x014 +#define LPC_LADR3L_BT 0x018 + +#define BT_CR1 0x4C +#define BT_CR1_IRQ_H2B 0x04 +#define BT_CR1_IRQ_HWRST 0x40 + +#define BT_CSR1 0x54 +#define BT_CSR1_IRQ_H2B 0x04 +#define BT_CSR1_IRQ_HWRST 0x40 + +#define BT_CTRL 0x58 +#define BT_CTRL_B_BUSY 0x80 +#define BT_CTRL_H_BUSY 0x40 +#define BT_CTRL_OEM0 0x20 +#define BT_CTRL_SMS_ATN 0x10 +#define BT_CTRL_B2H_ATN 0x08 +#define BT_CTRL_H2B_ATN 0x04 +#define BT_CTRL_CLR_RD_PTR 0x02 +#define BT_CTRL_CLR_WR_PTR 0x01 +#define BT_BMC2HOST 0x5C +#define BT_HOST2BMC 0x98 +#define BT_INTMASK 0x60 +#define BT_INTMASK_B2H_IRQEN 0x01 +#define BT_INTMASK_B2H_IRQ 0x02 +#define BT_INTMASK_BMC_HWRST 0x80 + +#define BT_BMC_BUFFER_SIZE 256 + +struct bt_bmc { + struct device dev; + struct miscdevice miscdev; + struct regmap *map; + int irq; + wait_queue_head_t queue; + struct timer_list poll_timer; + struct mutex mutex; +}; + +static atomic_t open_count = ATOMIC_INIT(0); + +static const struct regmap_config bt_regmap_cfg = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, +}; + +static u8 bt_inb(struct bt_bmc *bt_bmc, int reg) +{ + uint32_t val = 0; + int rc; + + rc = regmap_read(bt_bmc->map, reg, &val); + WARN(rc != 0, "regmap_read() failed: %d\n", rc); + + return rc == 0 ? (u8) val : 0; +} + +static void bt_outb(struct bt_bmc *bt_bmc, u8 data, int reg) +{ + int rc; + + rc = regmap_write(bt_bmc->map, reg, data); + WARN(rc != 0, "regmap_write() failed: %d\n", rc); +} + +static void clr_rd_ptr(struct bt_bmc *bt_bmc) +{ + bt_outb(bt_bmc, BT_CTRL_CLR_RD_PTR, BT_CTRL); +} + +static void clr_wr_ptr(struct bt_bmc *bt_bmc) +{ + bt_outb(bt_bmc, BT_CTRL_CLR_WR_PTR, BT_CTRL); +} + +static void clr_h2b_atn(struct bt_bmc *bt_bmc) +{ + bt_outb(bt_bmc, 0, BT_CTRL); +} + +static void set_b_busy(struct bt_bmc *bt_bmc) +{ + if (!(bt_inb(bt_bmc, BT_CTRL) & BT_CTRL_B_BUSY)) + bt_outb(bt_bmc, BT_CTRL_B_BUSY, BT_CTRL); +} + +static void clr_b_busy(struct bt_bmc *bt_bmc) +{ + if (bt_inb(bt_bmc, BT_CTRL) & BT_CTRL_B_BUSY) + bt_outb(bt_bmc, 0, BT_CTRL); +} + +static void set_b2h_atn(struct bt_bmc *bt_bmc) +{ + bt_outb(bt_bmc, BT_CTRL_B2H_ATN, BT_CTRL); +} + +static u8 bt_read(struct bt_bmc *bt_bmc) +{ + return bt_inb(bt_bmc, BT_HOST2BMC); +} + +static ssize_t bt_readn(struct bt_bmc *bt_bmc, u8 *buf, size_t n) +{ + int i; + + for (i = 0; i < n; i++) + buf[i] = bt_read(bt_bmc); + return n; +} + +static void bt_write(struct bt_bmc *bt_bmc, u8 c) +{ + bt_outb(bt_bmc, c, BT_BMC2HOST); +} + +static ssize_t bt_writen(struct bt_bmc *bt_bmc, u8 *buf, size_t n) +{ + int i; + + for (i = 0; i < n; i++) + bt_write(bt_bmc, buf[i]); + return n; +} + +static void set_sms_atn(struct bt_bmc *bt_bmc) +{ + bt_outb(bt_bmc, BT_CTRL_SMS_ATN, BT_CTRL); +} + +static struct bt_bmc *file_bt_bmc(struct file *file) +{ + return container_of(file->private_data, struct bt_bmc, miscdev); +} + +static int bt_bmc_open(struct inode *inode, struct file *file) +{ + struct bt_bmc *bt_bmc = file_bt_bmc(file); + + if (atomic_inc_return(&open_count) == 1) { + clr_b_busy(bt_bmc); + return 0; + } + + atomic_dec(&open_count); + + return -EBUSY; +} + +/* + * The BT (Block Transfer) interface means that entire messages are + * buffered by the host before a notification is sent to the BMC that + * there is data to be read. The first byte is the length and the + * message data follows. The read operation just tries to capture the + * whole before returning it to userspace. + * + * BT Message format : + * + * Byte 1 Byte 2 Byte 3 Byte 4 Byte 5:N + * Length NetFn/LUN Seq Cmd Data + * + */ +static ssize_t bt_bmc_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct bt_bmc *bt_bmc = file_bt_bmc(file); + u8 len; + int len_byte = 1; + u8 kbuffer[BT_BMC_BUFFER_SIZE]; + ssize_t ret = 0; + ssize_t nread; + + WARN_ON(*ppos); + + if (wait_event_interruptible(bt_bmc->queue, + bt_inb(bt_bmc, BT_CTRL) & BT_CTRL_H2B_ATN)) + return -ERESTARTSYS; + + mutex_lock(&bt_bmc->mutex); + + if (unlikely(!(bt_inb(bt_bmc, BT_CTRL) & BT_CTRL_H2B_ATN))) { + ret = -EIO; + goto out_unlock; + } + + set_b_busy(bt_bmc); + clr_h2b_atn(bt_bmc); + clr_rd_ptr(bt_bmc); + + /* + * The BT frames start with the message length, which does not + * include the length byte. + */ + kbuffer[0] = bt_read(bt_bmc); + len = kbuffer[0]; + + /* We pass the length back to userspace as well */ + if (len + 1 > count) + len = count - 1; + + while (len) { + nread = min_t(ssize_t, len, sizeof(kbuffer) - len_byte); + + bt_readn(bt_bmc, kbuffer + len_byte, nread); + + if (copy_to_user(buf, kbuffer, nread + len_byte)) { + ret = -EFAULT; + break; + } + len -= nread; + buf += nread + len_byte; + ret += nread + len_byte; + len_byte = 0; + } + + clr_b_busy(bt_bmc); + +out_unlock: + mutex_unlock(&bt_bmc->mutex); + return ret; +} + +/* + * BT Message response format : + * + * Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6:N + * Length NetFn/LUN Seq Cmd Code Data + */ +static ssize_t bt_bmc_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct bt_bmc *bt_bmc = file_bt_bmc(file); + u8 kbuffer[BT_BMC_BUFFER_SIZE]; + ssize_t ret = 0; + ssize_t nwritten; + + /* + * send a minimum response size + */ + if (count < 5) + return -EINVAL; + + WARN_ON(*ppos); + + /* + * There's no interrupt for clearing bmc busy so we have to + * poll + */ + if (wait_event_interruptible(bt_bmc->queue, + !(bt_inb(bt_bmc, BT_CTRL) & + (BT_CTRL_H_BUSY | BT_CTRL_B2H_ATN)))) + return -ERESTARTSYS; + + mutex_lock(&bt_bmc->mutex); + + if (unlikely(bt_inb(bt_bmc, BT_CTRL) & + (BT_CTRL_H_BUSY | BT_CTRL_B2H_ATN))) { + ret = -EIO; + goto out_unlock; + } + + clr_wr_ptr(bt_bmc); + + while (count) { + nwritten = min_t(ssize_t, count, sizeof(kbuffer)); + if (copy_from_user(&kbuffer, buf, nwritten)) { + ret = -EFAULT; + break; + } + + bt_writen(bt_bmc, kbuffer, nwritten); + + count -= nwritten; + buf += nwritten; + ret += nwritten; + } + + set_b2h_atn(bt_bmc); + +out_unlock: + mutex_unlock(&bt_bmc->mutex); + return ret; +} + +static long bt_bmc_ioctl(struct file *file, unsigned int cmd, + unsigned long param) +{ + struct bt_bmc *bt_bmc = file_bt_bmc(file); + + switch (cmd) { + case BT_BMC_IOCTL_SMS_ATN: + set_sms_atn(bt_bmc); + return 0; + } + return -EINVAL; +} + +static int bt_bmc_release(struct inode *inode, struct file *file) +{ + struct bt_bmc *bt_bmc = file_bt_bmc(file); + + atomic_dec(&open_count); + set_b_busy(bt_bmc); + return 0; +} + +static __poll_t bt_bmc_poll(struct file *file, poll_table *wait) +{ + struct bt_bmc *bt_bmc = file_bt_bmc(file); + __poll_t mask = 0; + u8 ctrl; + + poll_wait(file, &bt_bmc->queue, wait); + + ctrl = bt_inb(bt_bmc, BT_CTRL); + + if (ctrl & BT_CTRL_H2B_ATN) + mask |= EPOLLIN; + + if (!(ctrl & (BT_CTRL_H_BUSY | BT_CTRL_B2H_ATN))) + mask |= EPOLLOUT; + + return mask; +} + +static const struct file_operations bt_bmc_fops = { + .owner = THIS_MODULE, + .open = bt_bmc_open, + .read = bt_bmc_read, + .write = bt_bmc_write, + .release = bt_bmc_release, + .poll = bt_bmc_poll, + .unlocked_ioctl = bt_bmc_ioctl, +}; + +static void poll_timer(struct timer_list *t) +{ + struct bt_bmc *bt_bmc = from_timer(bt_bmc, t, poll_timer); + + bt_bmc->poll_timer.expires += msecs_to_jiffies(500); + wake_up(&bt_bmc->queue); + add_timer(&bt_bmc->poll_timer); +} + +static irqreturn_t bt_bmc_irq(int irq, void *arg) +{ + struct bt_bmc *bt_bmc = arg; + u32 reg, intmsk; + int rc; + + rc = regmap_read(bt_bmc->map, BT_CR1, ®); + if (rc) + return IRQ_NONE; + + reg &= BT_CR1_IRQ_H2B | BT_CR1_IRQ_HWRST; + if (!reg) + return IRQ_NONE; + + /* ack pending IRQs */ + regmap_write(bt_bmc->map, BT_CR1, 0); + + if (reg & BT_CR1_IRQ_HWRST) { + regmap_read(bt_bmc->map, BT_INTMASK, &intmsk); + if (intmsk & BT_INTMASK_BMC_HWRST) + regmap_write(bt_bmc->map, BT_INTMASK, 0); + } + + wake_up(&bt_bmc->queue); + return IRQ_HANDLED; +} + +static int bt_bmc_config_irq(struct bt_bmc *bt_bmc, + struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + int rc; + + bt_bmc->irq = platform_get_irq(pdev, 0); + if (!bt_bmc->irq) + return -ENODEV; + + rc = devm_request_irq(dev, bt_bmc->irq, bt_bmc_irq, IRQF_SHARED, + DEVICE_NAME, bt_bmc); + if (rc < 0) { + dev_warn(dev, "Unable to request IRQ %d\n", bt_bmc->irq); + bt_bmc->irq = 0; + return rc; + } + + /* + * Configure IRQs on the bmc clearing the H2B and HBUSY bits; + * H2B will be asserted when the bmc has data for us; HBUSY + * will be cleared (along with B2H) when we can write the next + * message to the BT buffer + */ + rc = regmap_update_bits(bt_bmc->map, BT_CSR1, + BT_CSR1_IRQ_H2B | BT_CSR1_IRQ_HWRST, + BT_CSR1_IRQ_H2B | BT_CSR1_IRQ_HWRST); + + return rc; +} + +static int bt_bmc_probe(struct platform_device *pdev) +{ + struct bt_bmc *bt_bmc; + struct device *dev; + int rc; + + if (!pdev || !pdev->dev.of_node) + return -ENODEV; + + dev = &pdev->dev; + dev_info(dev, "Found bt bmc device\n"); + + bt_bmc = devm_kzalloc(dev, sizeof(*bt_bmc), GFP_KERNEL); + if (!bt_bmc) + return -ENOMEM; + + dev_set_drvdata(&pdev->dev, bt_bmc); + + bt_bmc->map = syscon_node_to_regmap(pdev->dev.parent->of_node); + + mutex_init(&bt_bmc->mutex); + init_waitqueue_head(&bt_bmc->queue); + + bt_bmc->miscdev.minor = MISC_DYNAMIC_MINOR, + bt_bmc->miscdev.name = DEVICE_NAME, + bt_bmc->miscdev.fops = &bt_bmc_fops, + bt_bmc->miscdev.parent = dev; + rc = misc_register(&bt_bmc->miscdev); + if (rc) { + dev_err(dev, "Unable to register misc device\n"); + return rc; + } + + bt_bmc_config_irq(bt_bmc, pdev); + + if (bt_bmc->irq) { + dev_info(dev, "Using IRQ %d\n", bt_bmc->irq); + } else { + dev_info(dev, "No IRQ; using timer\n"); + timer_setup(&bt_bmc->poll_timer, poll_timer, 0); + bt_bmc->poll_timer.expires = jiffies + msecs_to_jiffies(10); + add_timer(&bt_bmc->poll_timer); + } + + regmap_update_bits(bt_bmc->map, LPC_HICR0, LPC_HICR0_LPC3E, LPC_HICR0_LPC3E); + regmap_update_bits(bt_bmc->map, LPC_HICR4, LPC_BTENABLE, LPC_BTENABLE); + regmap_write(bt_bmc->map, LPC_LADR3H_BT, BT_IO_BASE >> 8); + regmap_write(bt_bmc->map, LPC_LADR3L_BT, BT_IO_BASE); + regmap_update_bits(bt_bmc->map, LPC_HICR2, LPC_HICR2_IBFIF3, LPC_HICR2_IBFIF3); + clr_b_busy(bt_bmc); + + return 0; +} + +static int bt_bmc_remove(struct platform_device *pdev) +{ + struct bt_bmc *bt_bmc = dev_get_drvdata(&pdev->dev); + + misc_deregister(&bt_bmc->miscdev); + if (!bt_bmc->irq) + del_timer_sync(&bt_bmc->poll_timer); + + return 0; +} + +static const struct of_device_id bt_bmc_match[] = { + { .compatible = "phytium,bt-bmc" }, + { }, +}; +MODULE_DEVICE_TABLE(of, bt_bmc_match); + +static struct platform_driver bt_bmc_driver = { + .driver = { + .name = DEVICE_NAME, + .of_match_table = bt_bmc_match, + }, + .probe = bt_bmc_probe, + .remove = bt_bmc_remove, +}; + +module_platform_driver(bt_bmc_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Cheng Quan