diff options
Diffstat (limited to 'drivers/char/ipmi/ipmi_si_ls2k.c')
| -rw-r--r-- | drivers/char/ipmi/ipmi_si_ls2k.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/drivers/char/ipmi/ipmi_si_ls2k.c b/drivers/char/ipmi/ipmi_si_ls2k.c new file mode 100644 index 000000000000..45442c257efd --- /dev/null +++ b/drivers/char/ipmi/ipmi_si_ls2k.c @@ -0,0 +1,189 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Driver for Loongson-2K BMC IPMI interface + * + * Copyright (C) 2024-2025 Loongson Technology Corporation Limited. + * + * Authors: + * Chong Qiao <qiaochong@loongson.cn> + * Binbin Zhou <zhoubinbin@loongson.cn> + */ + +#include <linux/bitfield.h> +#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/types.h> + +#include "ipmi_si.h" + +#define LS2K_KCS_FIFO_IBFH 0x0 +#define LS2K_KCS_FIFO_IBFT 0x1 +#define LS2K_KCS_FIFO_OBFH 0x2 +#define LS2K_KCS_FIFO_OBFT 0x3 + +/* KCS registers */ +#define LS2K_KCS_REG_STS 0x4 +#define LS2K_KCS_REG_DATA_OUT 0x5 +#define LS2K_KCS_REG_DATA_IN 0x6 +#define LS2K_KCS_REG_CMD 0x8 + +#define LS2K_KCS_CMD_DATA 0xa +#define LS2K_KCS_VERSION 0xb +#define LS2K_KCS_WR_REQ 0xc +#define LS2K_KCS_WR_ACK 0x10 + +#define LS2K_KCS_STS_OBF BIT(0) +#define LS2K_KCS_STS_IBF BIT(1) +#define LS2K_KCS_STS_SMS_ATN BIT(2) +#define LS2K_KCS_STS_CMD BIT(3) + +#define LS2K_KCS_DATA_MASK (LS2K_KCS_STS_OBF | LS2K_KCS_STS_IBF | LS2K_KCS_STS_CMD) + +static bool ls2k_registered; + +static unsigned char ls2k_mem_inb_v0(const struct si_sm_io *io, unsigned int offset) +{ + void __iomem *addr = io->addr; + int reg_offset; + + if (offset & BIT(0)) { + reg_offset = LS2K_KCS_REG_STS; + } else { + writeb(readb(addr + LS2K_KCS_REG_STS) & ~LS2K_KCS_STS_OBF, addr + LS2K_KCS_REG_STS); + reg_offset = LS2K_KCS_REG_DATA_OUT; + } + + return readb(addr + reg_offset); +} + +static unsigned char ls2k_mem_inb_v1(const struct si_sm_io *io, unsigned int offset) +{ + void __iomem *addr = io->addr; + unsigned char inb = 0, cmd; + bool obf, ibf; + + obf = readb(addr + LS2K_KCS_FIFO_OBFH) ^ readb(addr + LS2K_KCS_FIFO_OBFT); + ibf = readb(addr + LS2K_KCS_FIFO_IBFH) ^ readb(addr + LS2K_KCS_FIFO_IBFT); + cmd = readb(addr + LS2K_KCS_CMD_DATA); + + if (offset & BIT(0)) { + inb = readb(addr + LS2K_KCS_REG_STS) & ~LS2K_KCS_DATA_MASK; + inb |= FIELD_PREP(LS2K_KCS_STS_OBF, obf) + | FIELD_PREP(LS2K_KCS_STS_IBF, ibf) + | FIELD_PREP(LS2K_KCS_STS_CMD, cmd); + } else { + inb = readb(addr + LS2K_KCS_REG_DATA_OUT); + writeb(readb(addr + LS2K_KCS_FIFO_OBFH), addr + LS2K_KCS_FIFO_OBFT); + } + + return inb; +} + +static void ls2k_mem_outb_v0(const struct si_sm_io *io, unsigned int offset, + unsigned char val) +{ + void __iomem *addr = io->addr; + unsigned char sts = readb(addr + LS2K_KCS_REG_STS); + int reg_offset; + + if (sts & LS2K_KCS_STS_IBF) + return; + + if (offset & BIT(0)) { + reg_offset = LS2K_KCS_REG_CMD; + sts |= LS2K_KCS_STS_CMD; + } else { + reg_offset = LS2K_KCS_REG_DATA_IN; + sts &= ~LS2K_KCS_STS_CMD; + } + + writew(val, addr + reg_offset); + writeb(sts | LS2K_KCS_STS_IBF, addr + LS2K_KCS_REG_STS); + writel(readl(addr + LS2K_KCS_WR_REQ) + 1, addr + LS2K_KCS_WR_REQ); +} + +static void ls2k_mem_outb_v1(const struct si_sm_io *io, unsigned int offset, + unsigned char val) +{ + void __iomem *addr = io->addr; + unsigned char ibfh, ibft; + int reg_offset; + + ibfh = readb(addr + LS2K_KCS_FIFO_IBFH); + ibft = readb(addr + LS2K_KCS_FIFO_IBFT); + + if (ibfh ^ ibft) + return; + + reg_offset = (offset & BIT(0)) ? LS2K_KCS_REG_CMD : LS2K_KCS_REG_DATA_IN; + writew(val, addr + reg_offset); + + writeb(offset & BIT(0), addr + LS2K_KCS_CMD_DATA); + writeb(!ibft, addr + LS2K_KCS_FIFO_IBFH); + writel(readl(addr + LS2K_KCS_WR_REQ) + 1, addr + LS2K_KCS_WR_REQ); +} + +static void ls2k_mem_cleanup(struct si_sm_io *io) +{ + if (io->addr) + iounmap(io->addr); +} + +static int ipmi_ls2k_mem_setup(struct si_sm_io *io) +{ + unsigned char version; + + io->addr = ioremap(io->addr_data, io->regspacing); + if (!io->addr) + return -EIO; + + version = readb(io->addr + LS2K_KCS_VERSION); + + io->inputb = version ? ls2k_mem_inb_v1 : ls2k_mem_inb_v0; + io->outputb = version ? ls2k_mem_outb_v1 : ls2k_mem_outb_v0; + io->io_cleanup = ls2k_mem_cleanup; + + return 0; +} + +static int ipmi_ls2k_probe(struct platform_device *pdev) +{ + struct si_sm_io io; + + memset(&io, 0, sizeof(io)); + + io.si_info = &ipmi_kcs_si_info; + io.io_setup = ipmi_ls2k_mem_setup; + io.addr_data = pdev->resource[0].start; + io.regspacing = resource_size(&pdev->resource[0]); + io.dev = &pdev->dev; + + dev_dbg(&pdev->dev, "addr 0x%lx, spacing %d.\n", io.addr_data, io.regspacing); + + return ipmi_si_add_smi(&io); +} + +static void ipmi_ls2k_remove(struct platform_device *pdev) +{ + ipmi_si_remove_by_dev(&pdev->dev); +} + +struct platform_driver ipmi_ls2k_platform_driver = { + .driver = { + .name = "ls2k-ipmi-si", + }, + .probe = ipmi_ls2k_probe, + .remove = ipmi_ls2k_remove, +}; + +void ipmi_si_ls2k_init(void) +{ + platform_driver_register(&ipmi_ls2k_platform_driver); + ls2k_registered = true; +} + +void ipmi_si_ls2k_shutdown(void) +{ + if (ls2k_registered) + platform_driver_unregister(&ipmi_ls2k_platform_driver); +} |