// SPDX-License-Identifier: GPL-2.0-or-later /* * X-Gene SLIMpro I2C Driver * * Copyright (c) 2014, Applied Micro Circuits Corporation * Author: Feng Kan * Author: Hieu Le * * This driver provides support for X-Gene SLIMpro I2C device access * using the APM X-Gene SLIMpro mailbox driver. */ #include #include #include #include #include #include #include #include #include #include #include #define MAILBOX_OP_TIMEOUT 1000 /* Operation time out in ms */ #define MAILBOX_I2C_INDEX 0 #define SLIMPRO_IIC_BUS 1 /* Use I2C bus 1 only */ #define SMBUS_CMD_LEN 1 #define BYTE_DATA 1 #define WORD_DATA 2 #define BLOCK_DATA 3 #define SLIMPRO_IIC_I2C_PROTOCOL 0 #define SLIMPRO_IIC_SMB_PROTOCOL 1 #define SLIMPRO_IIC_READ 0 #define SLIMPRO_IIC_WRITE 1 #define IIC_SMB_WITHOUT_DATA_LEN 0 #define IIC_SMB_WITH_DATA_LEN 1 #define SLIMPRO_DEBUG_MSG 0 #define SLIMPRO_MSG_TYPE_SHIFT 28 #define SLIMPRO_DBG_SUBTYPE_I2C1READ 4 #define SLIMPRO_DBGMSG_TYPE_SHIFT 24 #define SLIMPRO_DBGMSG_TYPE_MASK 0x0F000000U #define SLIMPRO_IIC_DEV_SHIFT 23 #define SLIMPRO_IIC_DEV_MASK 0x00800000U #define SLIMPRO_IIC_DEVID_SHIFT 13 #define SLIMPRO_IIC_DEVID_MASK 0x007FE000U #define SLIMPRO_IIC_RW_SHIFT 12 #define SLIMPRO_IIC_RW_MASK 0x00001000U #define SLIMPRO_IIC_PROTO_SHIFT 11 #define SLIMPRO_IIC_PROTO_MASK 0x00000800U #define SLIMPRO_IIC_ADDRLEN_SHIFT 8 #define SLIMPRO_IIC_ADDRLEN_MASK 0x00000700U #define SLIMPRO_IIC_DATALEN_SHIFT 0 #define SLIMPRO_IIC_DATALEN_MASK 0x000000FFU /* * SLIMpro I2C message encode * * dev - Controller number (0-based) * chip - I2C chip address * op - SLIMPRO_IIC_READ or SLIMPRO_IIC_WRITE * proto - SLIMPRO_IIC_SMB_PROTOCOL or SLIMPRO_IIC_I2C_PROTOCOL * addrlen - Length of the address field * datalen - Length of the data field */ #define SLIMPRO_IIC_ENCODE_MSG(dev, chip, op, proto, addrlen, datalen) \ ((SLIMPRO_DEBUG_MSG << SLIMPRO_MSG_TYPE_SHIFT) | \ ((SLIMPRO_DBG_SUBTYPE_I2C1READ << SLIMPRO_DBGMSG_TYPE_SHIFT) & \ SLIMPRO_DBGMSG_TYPE_MASK) | \ ((dev << SLIMPRO_IIC_DEV_SHIFT) & SLIMPRO_IIC_DEV_MASK) | \ ((chip << SLIMPRO_IIC_DEVID_SHIFT) & SLIMPRO_IIC_DEVID_MASK) | \ ((op << SLIMPRO_IIC_RW_SHIFT) & SLIMPRO_IIC_RW_MASK) | \ ((proto << SLIMPRO_IIC_PROTO_SHIFT) & SLIMPRO_IIC_PROTO_MASK) | \ ((addrlen << SLIMPRO_IIC_ADDRLEN_SHIFT) & SLIMPRO_IIC_ADDRLEN_MASK) | \ ((datalen << SLIMPRO_IIC_DATALEN_SHIFT) & SLIMPRO_IIC_DATALEN_MASK)) #define SLIMPRO_MSG_TYPE(v) (((v) & 0xF0000000) >> 28) /* * Encode for upper address for block data */ #define SLIMPRO_IIC_ENCODE_FLAG_BUFADDR 0x80000000 #define SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(a) ((u32) (((a) << 30) \ & 0x40000000)) #define SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(a) ((u32) (((a) >> 12) \ & 0x3FF00000)) #define SLIMPRO_IIC_ENCODE_ADDR(a) ((a) & 0x000FFFFF) #define SLIMPRO_IIC_MSG_DWORD_COUNT 3 /* PCC related defines */ #define PCC_SIGNATURE 0x50424300 #define PCC_STS_CMD_COMPLETE BIT(0) #define PCC_STS_SCI_DOORBELL BIT(1) #define PCC_STS_ERR BIT(2) #define PCC_STS_PLAT_NOTIFY BIT(3) #define PCC_CMD_GENERATE_DB_INT BIT(15) struct slimpro_i2c_dev { struct i2c_adapter adapter; struct device *dev; struct mbox_chan *mbox_chan; struct mbox_client mbox_client; int mbox_idx; struct completion rd_complete; u8 dma_buffer[I2C_SMBUS_BLOCK_MAX + 1]; /* dma_buffer[0] is used for length */ u32 *resp_msg; phys_addr_t comm_base_addr; void *pcc_comm_addr; }; #define to_slimpro_i2c_dev(cl) \ container_of(cl, struct slimpro_i2c_dev, mbox_client) enum slimpro_i2c_version { XGENE_SLIMPRO_I2C_V1 = 0, XGENE_SLIMPRO_I2C_V2 = 1, }; /* * This function tests and clears a bitmask then returns its old value */ static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask) { u16 ret, val; val = le16_to_cpu(READ_ONCE(*addr)); ret = val & mask; val &= ~mask; WRITE_ONCE(*addr, cpu_to_le16(val)); return ret; } static void slimpro_i2c_rx_cb(struct mbox_client *cl, void *mssg) { struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl); /* * Response message format: * mssg[0] is the return code of the operation * mssg[1] is the first data word * mssg[2] is NOT used */ if (ctx->resp_msg) *ctx->resp_msg = ((u32 *)mssg)[1]; if (ctx->mbox_client.tx_block) complete(&ctx->rd_complete); } static void slimpro_i2c_pcc_rx_cb(struct mbox_client *cl, void *msg) { struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl); struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr; /* Check if platform sends interrupt */ if (!xgene_word_tst_and_clr(&generic_comm_base->status, PCC_STS_SCI_DOORBELL)) return; if (xgene_word_tst_and_clr(&generic_comm_base->status, PCC_STS_CMD_COMPLETE)) { msg = generic_comm_base + 1; /* Response message msg[1] contains the return value. */ if (ctx->resp_msg) *ctx->resp_msg = ((u32 *)msg)[1]; complete(&ctx->rd_complete); } } static void slimpro_i2c_pcc_tx_prepare(struct slimpro_i2c_dev *ctx, u32 *msg) { struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr; u32 *ptr = (void *)(generic_comm_base + 1); u16 status; int i; WRITE_ONCE(generic_comm_base->signature, cpu_to_le32(PCC_SIGNATURE | ctx->mbox_idx)); WRITE_ONCE(generic_comm_base->command, cpu_to_le16(SLIMPRO_MSG_TYPE(msg[0]) | PCC_CMD_GENERATE_DB_INT)); status = le16_to_cpu(READ_ONCE(generic_comm_base->status)); status &= ~PCC_STS_CMD_COMPLETE; WRITE_ONCE(generic_comm_base->status, cpu_to_le16(status)); /* Copy the message to the PCC comm space */ for (i = 0; i < SLIMPRO_IIC_MSG_DWORD_COUNT; i++) WRITE_ONCE(ptr[i], cpu_to_le32(msg[i])); } static int start_i2c_msg_xfer(struct slimpro_i2c_dev *ctx) { if (ctx->mbox_client.tx_block || !acpi_disabled) { if (!wait_for_completion_timeout(&ctx->rd_complete, msecs_to_jiffies(MAILBOX_OP_TIMEOUT))) return -ETIMEDOUT; } /* Check of invalid data or no device */ if (*ctx->resp_msg == 0xffffffff) return -ENODEV; return 0; } static int slimpro_i2c_send_msg(struct slimpro_i2c_dev *ctx, u32 *msg, u32 *data) { int rc; ctx->resp_msg = data; if (!acpi_disabled) { reinit_completion(&ctx->rd_complete); slimpro_i2c_pcc_tx_prepare(ctx, msg); } rc = mbox_send_message(ctx->mbox_chan, msg); if (rc < 0) goto err; rc = start_i2c_msg_xfer(ctx); err: if (!acpi_disabled) mbox_chan_txdone(ctx->mbox_chan, 0); ctx->resp_msg = NULL; return rc; } static int slimpro_i2c_rd(struct slimpro_i2c_dev *ctx, u32 chip, u32 addr, u32 addrlen, u32 protocol, u32 readlen, u32 *data) { u32 msg[3]; msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_READ, protocol, addrlen, readlen); msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr); msg[2] = 0; return slimpro_i2c_send_msg(ctx, msg, data); } static int slimpro_i2c_wr(struct slimpro_i2c_dev *ctx, u32 chip, u32 addr, u32 addrlen, u32 protocol, u32 writelen, u32 data) { u32 msg[3]; msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_WRITE, protocol, addrlen, writelen); msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr); msg[2] = data; return slimpro_i2c_send_msg(ctx, msg, msg); } static int slimpro_i2c_blkrd(struct slimpro_i2c_dev *ctx, u32 chip, u32 addr, u32 addrlen, u32 protocol, u32 readlen, u32 with_data_len, void *data) { dma_addr_t paddr; u32 msg[3]; int rc; paddr = dma_map_single(ctx->dev, ctx->dma_buffer, readlen, DMA_FROM_DEVICE); if (dma_mapping_error(ctx->dev, paddr)) { dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n", ctx->dma_buffer); return -ENOMEM; } msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_READ, protocol, addrlen, readlen); msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR | SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(with_data_len) | SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) | SLIMPRO_IIC_ENCODE_ADDR(addr); msg[2] = (u32)paddr; rc = slimpro_i2c_send_msg(ctx, msg, msg); /* Copy to destination */ memcpy(data, ctx->dma_buffer, readlen); dma_unmap_single(ctx->dev, paddr, readlen, DMA_FROM_DEVICE); return rc; } static int slimpro_i2c_blkwr(struct slimpro_i2c_dev *ctx, u32 chip, u32 addr, u32 addrlen, u32 protocol, u32 writelen, void *data) { dma_addr_t paddr; u32 msg[3]; int rc; if (writelen > I2C_SMBUS_BLOCK_MAX) return -EINVAL; memcpy(ctx->dma_buffer, data, writelen); paddr = dma_map_single(ctx->dev, ctx->dma_buffer, writelen, DMA_TO_DEVICE); if (dma_mapping_error(ctx->dev, paddr)) { dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n", ctx->dma_buffer); return -ENOMEM; } msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_WRITE, protocol, addrlen, writelen); msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR | SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) | SLIMPRO_IIC_ENCODE_ADDR(addr); msg[2] = (u32)paddr; if (ctx->mbox_client.tx_block) reinit_completion(&ctx->rd_complete); rc = slimpro_i2c_send_msg(ctx, msg, msg); dma_unmap_single(ctx->dev, paddr, writelen, DMA_TO_DEVICE); return rc; } static int xgene_slimpro_i2c_xfer(struct i2c_adapter *adap, u16 addr, unsigned short flags, char read_write, u8 command, int size, union i2c_smbus_data *data) { struct slimpro_i2c_dev *ctx = i2c_get_adapdata(adap); int ret = -EOPNOTSUPP; u32 val; switch (size) { case I2C_SMBUS_BYTE: if (read_write == I2C_SMBUS_READ) { ret = slimpro_i2c_rd(ctx, addr, 0, 0, SLIMPRO_IIC_SMB_PROTOCOL, BYTE_DATA, &val); data->byte = val; } else { ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN, SLIMPRO_IIC_SMB_PROTOCOL, 0, 0); } break; case I2C_SMBUS_BYTE_DATA: if (read_write == I2C_SMBUS_READ) { ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN, SLIMPRO_IIC_SMB_PROTOCOL, BYTE_DATA, &val); data->byte = val; } else { val = data->byte; ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN, SLIMPRO_IIC_SMB_PROTOCOL, BYTE_DATA, val); } break; case I2C_SMBUS_WORD_DATA: if (read_write == I2C_SMBUS_READ) { ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN, SLIMPRO_IIC_SMB_PROTOCOL, WORD_DATA, &val); data->word = val; } else { val = data->word; ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN, SLIMPRO_IIC_SMB_PROTOCOL, WORD_DATA, val); } break; case I2C_SMBUS_BLOCK_DATA: if (read_write == I2C_SMBUS_READ) { ret = slimpro_i2c_blkrd(ctx, addr, command, SMBUS_CMD_LEN, SLIMPRO_IIC_SMB_PROTOCOL, I2C_SMBUS_BLOCK_MAX + 1, IIC_SMB_WITH_DATA_LEN, &data->block[0]); } else { ret = slimpro_i2c_blkwr(ctx, addr, command, SMBUS_CMD_LEN, SLIMPRO_IIC_SMB_PROTOCOL, data->block[0] + 1, &data->block[0]); } break; case I2C_SMBUS_I2C_BLOCK_DATA: if (read_write == I2C_SMBUS_READ) { ret = slimpro_i2c_blkrd(ctx, addr, command, SMBUS_CMD_LEN, SLIMPRO_IIC_I2C_PROTOCOL, I2C_SMBUS_BLOCK_MAX, IIC_SMB_WITHOUT_DATA_LEN, &data->block[1]); } else { ret = slimpro_i2c_blkwr(ctx, addr, command, SMBUS_CMD_LEN, SLIMPRO_IIC_I2C_PROTOCOL, data->block[0], &data->block[1]); } break; default: break; } return ret; } /* * Return list of supported functionality. */ static u32 xgene_slimpro_i2c_func(struct i2c_adapter *adapter) { return I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_I2C_BLOCK; } static const struct i2c_algorithm xgene_slimpro_i2c_algorithm = { .smbus_xfer = xgene_slimpro_i2c_xfer, .functionality = xgene_slimpro_i2c_func, }; static int xgene_slimpro_i2c_probe(struct platform_device *pdev) { struct slimpro_i2c_dev *ctx; struct i2c_adapter *adapter; struct mbox_client *cl; int rc; ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); if (!ctx) return -ENOMEM; ctx->dev = &pdev->dev; platform_set_drvdata(pdev, ctx); cl = &ctx->mbox_client; /* Request mailbox channel */ cl->dev = &pdev->dev; init_completion(&ctx->rd_complete); cl->tx_tout = MAILBOX_OP_TIMEOUT; cl->knows_txdone = false; if (acpi_disabled) { cl->tx_block = true; cl->rx_callback = slimpro_i2c_rx_cb; ctx->mbox_chan = mbox_request_channel(cl, MAILBOX_I2C_INDEX); if (IS_ERR(ctx->mbox_chan)) { dev_err(&pdev->dev, "i2c mailbox channel request failed\n"); return PTR_ERR(ctx->mbox_chan); } } else { struct acpi_pcct_hw_reduced *cppc_ss; const struct acpi_device_id *acpi_id; int version = XGENE_SLIMPRO_I2C_V1; acpi_id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev); if (!acpi_id) return -EINVAL; version = (int)acpi_id->driver_data; if (device_property_read_u32(&pdev->dev, "pcc-channel", &ctx->mbox_idx)) ctx->mbox_idx = MAILBOX_I2C_INDEX; cl->tx_block = false; cl->rx_callback = slimpro_i2c_pcc_rx_cb; ctx->mbox_chan = pcc_mbox_request_channel(cl, ctx->mbox_idx); if (IS_ERR(ctx->mbox_chan)) { dev_err(&pdev->dev, "PCC mailbox channel request failed\n"); return PTR_ERR(ctx->mbox_chan); } /* * The PCC mailbox controller driver should * have parsed the PCCT (global table of all * PCC channels) and stored pointers to the * subspace communication region in con_priv. */ cppc_ss = ctx->mbox_chan->con_priv; if (!cppc_ss) { dev_err(&pdev->dev, "PPC subspace not found\n"); rc = -ENOENT; goto mbox_err; } if (!ctx->mbox_chan->mbox->txdone_irq) { dev_err(&pdev->dev, "PCC IRQ not supported\n"); rc = -ENOENT; goto mbox_err; } /* * This is the shared communication region * for the OS and Platform to communicate over. */ ctx->comm_base_addr = cppc_ss->base_address; if (ctx->comm_base_addr) { if (version == XGENE_SLIMPRO_I2C_V2) ctx->pcc_comm_addr = memremap( ctx->comm_base_addr, cppc_ss->length, MEMREMAP_WT); else ctx->pcc_comm_addr = memremap( ctx->comm_base_addr, cppc_ss->length, MEMREMAP_WB); } else { dev_err(&pdev->dev, "Failed to get PCC comm region\n"); rc = -ENOENT; goto mbox_err; } if (!ctx->pcc_comm_addr) { dev_err(&pdev->dev, "Failed to ioremap PCC comm region\n"); rc = -ENOMEM; goto mbox_err; } } rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); if (rc) dev_warn(&pdev->dev, "Unable to set dma mask\n"); /* Setup I2C adapter */ adapter = &ctx->adapter; snprintf(adapter->name, sizeof(adapter->name), "MAILBOX I2C"); adapter->algo = &xgene_slimpro_i2c_algorithm; adapter->class = I2C_CLASS_HWMON; adapter->dev.parent = &pdev->dev; adapter->dev.of_node = pdev->dev.of_node; ACPI_COMPANION_SET(&adapter->dev, ACPI_COMPANION(&pdev->dev)); i2c_set_adapdata(adapter, ctx); rc = i2c_add_adapter(adapter); if (rc) goto mbox_err; dev_info(&pdev->dev, "Mailbox I2C Adapter registered\n"); return 0; mbox_err: if (acpi_disabled) mbox_free_channel(ctx->mbox_chan); else pcc_mbox_free_channel(ctx->mbox_chan); return rc; } static int xgene_slimpro_i2c_remove(struct platform_device *pdev) { struct slimpro_i2c_dev *ctx = platform_get_drvdata(pdev); i2c_del_adapter(&ctx->adapter); if (acpi_disabled) mbox_free_channel(ctx->mbox_chan); else pcc_mbox_free_channel(ctx->mbox_chan); return 0; } static const struct of_device_id xgene_slimpro_i2c_dt_ids[] = { {.compatible = "apm,xgene-slimpro-i2c" }, {}, }; MODULE_DEVICE_TABLE(of, xgene_slimpro_i2c_dt_ids); #ifdef CONFIG_ACPI static const struct acpi_device_id xgene_slimpro_i2c_acpi_ids[] = { {"APMC0D40", XGENE_SLIMPRO_I2C_V1}, {"APMC0D8B", XGENE_SLIMPRO_I2C_V2}, {} }; MODULE_DEVICE_TABLE(acpi, xgene_slimpro_i2c_acpi_ids); #endif static struct platform_driver xgene_slimpro_i2c_driver = { .probe = xgene_slimpro_i2c_probe, .remove = xgene_slimpro_i2c_remove, .driver = { .name = "xgene-slimpro-i2c", .of_match_table = of_match_ptr(xgene_slimpro_i2c_dt_ids), .acpi_match_table = ACPI_PTR(xgene_slimpro_i2c_acpi_ids) }, }; module_platform_driver(xgene_slimpro_i2c_driver); MODULE_DESCRIPTION("APM X-Gene SLIMpro I2C driver"); MODULE_AUTHOR("Feng Kan "); MODULE_AUTHOR("Hieu Le "); MODULE_LICENSE("GPL");