diff options
Diffstat (limited to 'drivers/char/ipmi/kcs_bmc_aspeed.c')
| -rw-r--r-- | drivers/char/ipmi/kcs_bmc_aspeed.c | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/drivers/char/ipmi/kcs_bmc_aspeed.c b/drivers/char/ipmi/kcs_bmc_aspeed.c new file mode 100644 index 000000000..3c955946e --- /dev/null +++ b/drivers/char/ipmi/kcs_bmc_aspeed.c @@ -0,0 +1,320 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2015-2018, Intel Corporation. + */ + +#define pr_fmt(fmt) "aspeed-kcs-bmc: " fmt + +#include <linux/atomic.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/poll.h> +#include <linux/regmap.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/timer.h> + +#include "kcs_bmc.h" + + +#define DEVICE_NAME "ast-kcs-bmc" + +#define KCS_CHANNEL_MAX 4 + +/* mapped to lpc-bmc@0 IO space */ +#define LPC_HICR0 0x000 +#define LPC_HICR0_LPC3E BIT(7) +#define LPC_HICR0_LPC2E BIT(6) +#define LPC_HICR0_LPC1E BIT(5) +#define LPC_HICR2 0x008 +#define LPC_HICR2_IBFIF3 BIT(3) +#define LPC_HICR2_IBFIF2 BIT(2) +#define LPC_HICR2_IBFIF1 BIT(1) +#define LPC_HICR4 0x010 +#define LPC_HICR4_LADR12AS BIT(7) +#define LPC_HICR4_KCSENBL BIT(2) +#define LPC_LADR3H 0x014 +#define LPC_LADR3L 0x018 +#define LPC_LADR12H 0x01C +#define LPC_LADR12L 0x020 +#define LPC_IDR1 0x024 +#define LPC_IDR2 0x028 +#define LPC_IDR3 0x02C +#define LPC_ODR1 0x030 +#define LPC_ODR2 0x034 +#define LPC_ODR3 0x038 +#define LPC_STR1 0x03C +#define LPC_STR2 0x040 +#define LPC_STR3 0x044 + +/* mapped to lpc-host@80 IO space */ +#define LPC_HICRB 0x080 +#define LPC_HICRB_IBFIF4 BIT(1) +#define LPC_HICRB_LPC4E BIT(0) +#define LPC_LADR4 0x090 +#define LPC_IDR4 0x094 +#define LPC_ODR4 0x098 +#define LPC_STR4 0x09C + +struct aspeed_kcs_bmc { + struct regmap *map; +}; + + +static u8 aspeed_kcs_inb(struct kcs_bmc *kcs_bmc, u32 reg) +{ + struct aspeed_kcs_bmc *priv = kcs_bmc_priv(kcs_bmc); + u32 val = 0; + int rc; + + rc = regmap_read(priv->map, reg, &val); + WARN(rc != 0, "regmap_read() failed: %d\n", rc); + + return rc == 0 ? (u8) val : 0; +} + +static void aspeed_kcs_outb(struct kcs_bmc *kcs_bmc, u32 reg, u8 data) +{ + struct aspeed_kcs_bmc *priv = kcs_bmc_priv(kcs_bmc); + int rc; + + rc = regmap_write(priv->map, reg, data); + WARN(rc != 0, "regmap_write() failed: %d\n", rc); +} + + +/* + * AST_usrGuide_KCS.pdf + * 2. Background: + * we note D for Data, and C for Cmd/Status, default rules are + * A. KCS1 / KCS2 ( D / C:X / X+4 ) + * D / C : CA0h / CA4h + * D / C : CA8h / CACh + * B. KCS3 ( D / C:XX2h / XX3h ) + * D / C : CA2h / CA3h + * D / C : CB2h / CB3h + * C. KCS4 + * D / C : CA4h / CA5h + */ +static void aspeed_kcs_set_address(struct kcs_bmc *kcs_bmc, u16 addr) +{ + struct aspeed_kcs_bmc *priv = kcs_bmc_priv(kcs_bmc); + + switch (kcs_bmc->channel) { + case 1: + regmap_update_bits(priv->map, LPC_HICR4, + LPC_HICR4_LADR12AS, 0); + regmap_write(priv->map, LPC_LADR12H, addr >> 8); + regmap_write(priv->map, LPC_LADR12L, addr & 0xFF); + break; + + case 2: + regmap_update_bits(priv->map, LPC_HICR4, + LPC_HICR4_LADR12AS, LPC_HICR4_LADR12AS); + regmap_write(priv->map, LPC_LADR12H, addr >> 8); + regmap_write(priv->map, LPC_LADR12L, addr & 0xFF); + break; + + case 3: + regmap_write(priv->map, LPC_LADR3H, addr >> 8); + regmap_write(priv->map, LPC_LADR3L, addr & 0xFF); + break; + + case 4: + regmap_write(priv->map, LPC_LADR4, ((addr + 1) << 16) | + addr); + break; + + default: + break; + } +} + +static void aspeed_kcs_enable_channel(struct kcs_bmc *kcs_bmc, bool enable) +{ + struct aspeed_kcs_bmc *priv = kcs_bmc_priv(kcs_bmc); + + switch (kcs_bmc->channel) { + case 1: + if (enable) { + regmap_update_bits(priv->map, LPC_HICR2, + LPC_HICR2_IBFIF1, LPC_HICR2_IBFIF1); + regmap_update_bits(priv->map, LPC_HICR0, + LPC_HICR0_LPC1E, LPC_HICR0_LPC1E); + } else { + regmap_update_bits(priv->map, LPC_HICR0, + LPC_HICR0_LPC1E, 0); + regmap_update_bits(priv->map, LPC_HICR2, + LPC_HICR2_IBFIF1, 0); + } + break; + + case 2: + if (enable) { + regmap_update_bits(priv->map, LPC_HICR2, + LPC_HICR2_IBFIF2, LPC_HICR2_IBFIF2); + regmap_update_bits(priv->map, LPC_HICR0, + LPC_HICR0_LPC2E, LPC_HICR0_LPC2E); + } else { + regmap_update_bits(priv->map, LPC_HICR0, + LPC_HICR0_LPC2E, 0); + regmap_update_bits(priv->map, LPC_HICR2, + LPC_HICR2_IBFIF2, 0); + } + break; + + case 3: + if (enable) { + regmap_update_bits(priv->map, LPC_HICR2, + LPC_HICR2_IBFIF3, LPC_HICR2_IBFIF3); + regmap_update_bits(priv->map, LPC_HICR0, + LPC_HICR0_LPC3E, LPC_HICR0_LPC3E); + regmap_update_bits(priv->map, LPC_HICR4, + LPC_HICR4_KCSENBL, LPC_HICR4_KCSENBL); + } else { + regmap_update_bits(priv->map, LPC_HICR0, + LPC_HICR0_LPC3E, 0); + regmap_update_bits(priv->map, LPC_HICR4, + LPC_HICR4_KCSENBL, 0); + regmap_update_bits(priv->map, LPC_HICR2, + LPC_HICR2_IBFIF3, 0); + } + break; + + case 4: + if (enable) + regmap_update_bits(priv->map, LPC_HICRB, + LPC_HICRB_IBFIF4 | LPC_HICRB_LPC4E, + LPC_HICRB_IBFIF4 | LPC_HICRB_LPC4E); + else + regmap_update_bits(priv->map, LPC_HICRB, + LPC_HICRB_IBFIF4 | LPC_HICRB_LPC4E, + 0); + break; + + default: + break; + } +} + +static irqreturn_t aspeed_kcs_irq(int irq, void *arg) +{ + struct kcs_bmc *kcs_bmc = arg; + + if (!kcs_bmc_handle_event(kcs_bmc)) + return IRQ_HANDLED; + + return IRQ_NONE; +} + +static int aspeed_kcs_config_irq(struct kcs_bmc *kcs_bmc, + struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + int irq; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + return devm_request_irq(dev, irq, aspeed_kcs_irq, IRQF_SHARED, + dev_name(dev), kcs_bmc); +} + +static const struct kcs_ioreg ast_kcs_bmc_ioregs[KCS_CHANNEL_MAX] = { + { .idr = LPC_IDR1, .odr = LPC_ODR1, .str = LPC_STR1 }, + { .idr = LPC_IDR2, .odr = LPC_ODR2, .str = LPC_STR2 }, + { .idr = LPC_IDR3, .odr = LPC_ODR3, .str = LPC_STR3 }, + { .idr = LPC_IDR4, .odr = LPC_ODR4, .str = LPC_STR4 }, +}; + +static int aspeed_kcs_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct aspeed_kcs_bmc *priv; + struct kcs_bmc *kcs_bmc; + u32 chan, addr; + int rc; + + rc = of_property_read_u32(dev->of_node, "kcs_chan", &chan); + if ((rc != 0) || (chan == 0 || chan > KCS_CHANNEL_MAX)) { + dev_err(dev, "no valid 'kcs_chan' configured\n"); + return -ENODEV; + } + + rc = of_property_read_u32(dev->of_node, "kcs_addr", &addr); + if (rc) { + dev_err(dev, "no valid 'kcs_addr' configured\n"); + return -ENODEV; + } + + kcs_bmc = kcs_bmc_alloc(dev, sizeof(*priv), chan); + if (!kcs_bmc) + return -ENOMEM; + + priv = kcs_bmc_priv(kcs_bmc); + priv->map = syscon_node_to_regmap(dev->parent->of_node); + if (IS_ERR(priv->map)) { + dev_err(dev, "Couldn't get regmap\n"); + return -ENODEV; + } + + kcs_bmc->ioreg = ast_kcs_bmc_ioregs[chan - 1]; + kcs_bmc->io_inputb = aspeed_kcs_inb; + kcs_bmc->io_outputb = aspeed_kcs_outb; + + dev_set_drvdata(dev, kcs_bmc); + + aspeed_kcs_set_address(kcs_bmc, addr); + aspeed_kcs_enable_channel(kcs_bmc, true); + rc = aspeed_kcs_config_irq(kcs_bmc, pdev); + if (rc) + return rc; + + rc = misc_register(&kcs_bmc->miscdev); + if (rc) { + dev_err(dev, "Unable to register device\n"); + return rc; + } + + pr_info("channel=%u addr=0x%x idr=0x%x odr=0x%x str=0x%x\n", + chan, addr, + kcs_bmc->ioreg.idr, kcs_bmc->ioreg.odr, kcs_bmc->ioreg.str); + + return 0; +} + +static int aspeed_kcs_remove(struct platform_device *pdev) +{ + struct kcs_bmc *kcs_bmc = dev_get_drvdata(&pdev->dev); + + misc_deregister(&kcs_bmc->miscdev); + + return 0; +} + +static const struct of_device_id ast_kcs_bmc_match[] = { + { .compatible = "aspeed,ast2400-kcs-bmc" }, + { .compatible = "aspeed,ast2500-kcs-bmc" }, + { } +}; +MODULE_DEVICE_TABLE(of, ast_kcs_bmc_match); + +static struct platform_driver ast_kcs_bmc_driver = { + .driver = { + .name = DEVICE_NAME, + .of_match_table = ast_kcs_bmc_match, + }, + .probe = aspeed_kcs_probe, + .remove = aspeed_kcs_remove, +}; +module_platform_driver(ast_kcs_bmc_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Haiyue Wang <haiyue.wang@linux.intel.com>"); +MODULE_DESCRIPTION("Aspeed device interface to the KCS BMC device"); |