diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-xgene-slimpro.c')
-rw-r--r-- | drivers/i2c/busses/i2c-xgene-slimpro.c | 617 |
1 files changed, 617 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-xgene-slimpro.c b/drivers/i2c/busses/i2c-xgene-slimpro.c new file mode 100644 index 000000000..76e9dcd63 --- /dev/null +++ b/drivers/i2c/busses/i2c-xgene-slimpro.c @@ -0,0 +1,617 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X-Gene SLIMpro I2C Driver + * + * Copyright (c) 2014, Applied Micro Circuits Corporation + * Author: Feng Kan <fkan@apm.com> + * Author: Hieu Le <hnle@apm.com> + * + * This driver provides support for X-Gene SLIMpro I2C device access + * using the APM X-Gene SLIMpro mailbox driver. + */ +#include <acpi/pcc.h> +#include <linux/acpi.h> +#include <linux/dma-mapping.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/mailbox_client.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/version.h> + +#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 <fkan@apm.com>"); +MODULE_AUTHOR("Hieu Le <hnle@apm.com>"); +MODULE_LICENSE("GPL"); |