/* * This file is provided under a dual BSD/GPLv2 license. When using or * redistributing this file, you may do so under either license. * * Copyright(c) 2012 Intel Corporation. All rights reserved. * * GPL LICENSE SUMMARY * * This program is free software; you can redistribute it and/or modify * it under the terms of version 2 of the GNU General Public License as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * The full GNU General Public License is included in this distribution * in the file called LICENSE.GPL. * * BSD LICENSE * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * Neither the name of Intel Corporation nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* * Supports the SMBus Message Transport (SMT) in the Intel Atom Processor * S12xx Product Family. * * Features supported by this driver: * Hardware PEC yes * Block buffer yes * Block process call transaction no * Slave mode no */ #include #include #include #include #include #include #include #include #include #include /* PCI Address Constants */ #define SMBBAR 0 /* PCI DIDs for the Intel SMBus Message Transport (SMT) Devices */ #define PCI_DEVICE_ID_INTEL_S1200_SMT0 0x0c59 #define PCI_DEVICE_ID_INTEL_S1200_SMT1 0x0c5a #define PCI_DEVICE_ID_INTEL_AVOTON_SMT 0x1f15 #define ISMT_DESC_ENTRIES 2 /* number of descriptor entries */ #define ISMT_MAX_RETRIES 3 /* number of SMBus retries to attempt */ /* Hardware Descriptor Constants - Control Field */ #define ISMT_DESC_CWRL 0x01 /* Command/Write Length */ #define ISMT_DESC_BLK 0X04 /* Perform Block Transaction */ #define ISMT_DESC_FAIR 0x08 /* Set fairness flag upon successful arbit. */ #define ISMT_DESC_PEC 0x10 /* Packet Error Code */ #define ISMT_DESC_I2C 0x20 /* I2C Enable */ #define ISMT_DESC_INT 0x40 /* Interrupt */ #define ISMT_DESC_SOE 0x80 /* Stop On Error */ /* Hardware Descriptor Constants - Status Field */ #define ISMT_DESC_SCS 0x01 /* Success */ #define ISMT_DESC_DLTO 0x04 /* Data Low Time Out */ #define ISMT_DESC_NAK 0x08 /* NAK Received */ #define ISMT_DESC_CRC 0x10 /* CRC Error */ #define ISMT_DESC_CLTO 0x20 /* Clock Low Time Out */ #define ISMT_DESC_COL 0x40 /* Collisions */ #define ISMT_DESC_LPR 0x80 /* Large Packet Received */ /* Macros */ #define ISMT_DESC_ADDR_RW(addr, rw) (((addr) << 1) | (rw)) /* iSMT General Register address offsets (SMBBAR + ) */ #define ISMT_GR_GCTRL 0x000 /* General Control */ #define ISMT_GR_SMTICL 0x008 /* SMT Interrupt Cause Location */ #define ISMT_GR_ERRINTMSK 0x010 /* Error Interrupt Mask */ #define ISMT_GR_ERRAERMSK 0x014 /* Error AER Mask */ #define ISMT_GR_ERRSTS 0x018 /* Error Status */ #define ISMT_GR_ERRINFO 0x01c /* Error Information */ /* iSMT Master Registers */ #define ISMT_MSTR_MDBA 0x100 /* Master Descriptor Base Address */ #define ISMT_MSTR_MCTRL 0x108 /* Master Control */ #define ISMT_MSTR_MSTS 0x10c /* Master Status */ #define ISMT_MSTR_MDS 0x110 /* Master Descriptor Size */ #define ISMT_MSTR_RPOLICY 0x114 /* Retry Policy */ /* iSMT Miscellaneous Registers */ #define ISMT_SPGT 0x300 /* SMBus PHY Global Timing */ /* General Control Register (GCTRL) bit definitions */ #define ISMT_GCTRL_TRST 0x04 /* Target Reset */ #define ISMT_GCTRL_KILL 0x08 /* Kill */ #define ISMT_GCTRL_SRST 0x40 /* Soft Reset */ /* Master Control Register (MCTRL) bit definitions */ #define ISMT_MCTRL_SS 0x01 /* Start/Stop */ #define ISMT_MCTRL_MEIE 0x10 /* Master Error Interrupt Enable */ #define ISMT_MCTRL_FMHP 0x00ff0000 /* Firmware Master Head Ptr (FMHP) */ /* Master Status Register (MSTS) bit definitions */ #define ISMT_MSTS_HMTP 0xff0000 /* HW Master Tail Pointer (HMTP) */ #define ISMT_MSTS_MIS 0x20 /* Master Interrupt Status (MIS) */ #define ISMT_MSTS_MEIS 0x10 /* Master Error Int Status (MEIS) */ #define ISMT_MSTS_IP 0x01 /* In Progress */ /* Master Descriptor Size (MDS) bit definitions */ #define ISMT_MDS_MASK 0xff /* Master Descriptor Size mask (MDS) */ /* SMBus PHY Global Timing Register (SPGT) bit definitions */ #define ISMT_SPGT_SPD_MASK 0xc0000000 /* SMBus Speed mask */ #define ISMT_SPGT_SPD_80K 0x00 /* 80 kHz */ #define ISMT_SPGT_SPD_100K (0x1 << 30) /* 100 kHz */ #define ISMT_SPGT_SPD_400K (0x2 << 30) /* 400 kHz */ #define ISMT_SPGT_SPD_1M (0x3 << 30) /* 1 MHz */ /* MSI Control Register (MSICTL) bit definitions */ #define ISMT_MSICTL_MSIE 0x01 /* MSI Enable */ /* iSMT Hardware Descriptor */ struct ismt_desc { u8 tgtaddr_rw; /* target address & r/w bit */ u8 wr_len_cmd; /* write length in bytes or a command */ u8 rd_len; /* read length */ u8 control; /* control bits */ u8 status; /* status bits */ u8 retry; /* collision retry and retry count */ u8 rxbytes; /* received bytes */ u8 txbytes; /* transmitted bytes */ u32 dptr_low; /* lower 32 bit of the data pointer */ u32 dptr_high; /* upper 32 bit of the data pointer */ } __packed; struct ismt_priv { struct i2c_adapter adapter; void __iomem *smba; /* PCI BAR */ struct pci_dev *pci_dev; struct ismt_desc *hw; /* descriptor virt base addr */ dma_addr_t io_rng_dma; /* descriptor HW base addr */ u8 head; /* ring buffer head pointer */ struct completion cmp; /* interrupt completion */ u8 dma_buffer[I2C_SMBUS_BLOCK_MAX + 1]; /* temp R/W data buffer */ bool using_msi; /* type of interrupt flag */ }; /** * ismt_ids - PCI device IDs supported by this driver */ static const struct pci_device_id ismt_ids[] = { { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT0) }, { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT1) }, { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_AVOTON_SMT) }, { 0, } }; MODULE_DEVICE_TABLE(pci, ismt_ids); /* Bus speed control bits for slow debuggers - refer to the docs for usage */ static unsigned int bus_speed; module_param(bus_speed, uint, S_IRUGO); MODULE_PARM_DESC(bus_speed, "Bus Speed in kHz (0 = BIOS default)"); /** * __ismt_desc_dump() - dump the contents of a specific descriptor */ static void __ismt_desc_dump(struct device *dev, const struct ismt_desc *desc) { dev_dbg(dev, "Descriptor struct: %p\n", desc); dev_dbg(dev, "\ttgtaddr_rw=0x%02X\n", desc->tgtaddr_rw); dev_dbg(dev, "\twr_len_cmd=0x%02X\n", desc->wr_len_cmd); dev_dbg(dev, "\trd_len= 0x%02X\n", desc->rd_len); dev_dbg(dev, "\tcontrol= 0x%02X\n", desc->control); dev_dbg(dev, "\tstatus= 0x%02X\n", desc->status); dev_dbg(dev, "\tretry= 0x%02X\n", desc->retry); dev_dbg(dev, "\trxbytes= 0x%02X\n", desc->rxbytes); dev_dbg(dev, "\ttxbytes= 0x%02X\n", desc->txbytes); dev_dbg(dev, "\tdptr_low= 0x%08X\n", desc->dptr_low); dev_dbg(dev, "\tdptr_high= 0x%08X\n", desc->dptr_high); } /** * ismt_desc_dump() - dump the contents of a descriptor for debug purposes * @priv: iSMT private data */ static void ismt_desc_dump(struct ismt_priv *priv) { struct device *dev = &priv->pci_dev->dev; struct ismt_desc *desc = &priv->hw[priv->head]; dev_dbg(dev, "Dump of the descriptor struct: 0x%X\n", priv->head); __ismt_desc_dump(dev, desc); } /** * ismt_gen_reg_dump() - dump the iSMT General Registers * @priv: iSMT private data */ static void ismt_gen_reg_dump(struct ismt_priv *priv) { struct device *dev = &priv->pci_dev->dev; dev_dbg(dev, "Dump of the iSMT General Registers\n"); dev_dbg(dev, " GCTRL.... : (0x%p)=0x%X\n", priv->smba + ISMT_GR_GCTRL, readl(priv->smba + ISMT_GR_GCTRL)); dev_dbg(dev, " SMTICL... : (0x%p)=0x%016llX\n", priv->smba + ISMT_GR_SMTICL, (long long unsigned int)readq(priv->smba + ISMT_GR_SMTICL)); dev_dbg(dev, " ERRINTMSK : (0x%p)=0x%X\n", priv->smba + ISMT_GR_ERRINTMSK, readl(priv->smba + ISMT_GR_ERRINTMSK)); dev_dbg(dev, " ERRAERMSK : (0x%p)=0x%X\n", priv->smba + ISMT_GR_ERRAERMSK, readl(priv->smba + ISMT_GR_ERRAERMSK)); dev_dbg(dev, " ERRSTS... : (0x%p)=0x%X\n", priv->smba + ISMT_GR_ERRSTS, readl(priv->smba + ISMT_GR_ERRSTS)); dev_dbg(dev, " ERRINFO.. : (0x%p)=0x%X\n", priv->smba + ISMT_GR_ERRINFO, readl(priv->smba + ISMT_GR_ERRINFO)); } /** * ismt_mstr_reg_dump() - dump the iSMT Master Registers * @priv: iSMT private data */ static void ismt_mstr_reg_dump(struct ismt_priv *priv) { struct device *dev = &priv->pci_dev->dev; dev_dbg(dev, "Dump of the iSMT Master Registers\n"); dev_dbg(dev, " MDBA..... : (0x%p)=0x%016llX\n", priv->smba + ISMT_MSTR_MDBA, (long long unsigned int)readq(priv->smba + ISMT_MSTR_MDBA)); dev_dbg(dev, " MCTRL.... : (0x%p)=0x%X\n", priv->smba + ISMT_MSTR_MCTRL, readl(priv->smba + ISMT_MSTR_MCTRL)); dev_dbg(dev, " MSTS..... : (0x%p)=0x%X\n", priv->smba + ISMT_MSTR_MSTS, readl(priv->smba + ISMT_MSTR_MSTS)); dev_dbg(dev, " MDS...... : (0x%p)=0x%X\n", priv->smba + ISMT_MSTR_MDS, readl(priv->smba + ISMT_MSTR_MDS)); dev_dbg(dev, " RPOLICY.. : (0x%p)=0x%X\n", priv->smba + ISMT_MSTR_RPOLICY, readl(priv->smba + ISMT_MSTR_RPOLICY)); dev_dbg(dev, " SPGT..... : (0x%p)=0x%X\n", priv->smba + ISMT_SPGT, readl(priv->smba + ISMT_SPGT)); } /** * ismt_submit_desc() - add a descriptor to the ring * @priv: iSMT private data */ static void ismt_submit_desc(struct ismt_priv *priv) { uint fmhp; uint val; ismt_desc_dump(priv); ismt_gen_reg_dump(priv); ismt_mstr_reg_dump(priv); /* Set the FMHP (Firmware Master Head Pointer)*/ fmhp = ((priv->head + 1) % ISMT_DESC_ENTRIES) << 16; val = readl(priv->smba + ISMT_MSTR_MCTRL); writel((val & ~ISMT_MCTRL_FMHP) | fmhp, priv->smba + ISMT_MSTR_MCTRL); /* Set the start bit */ val = readl(priv->smba + ISMT_MSTR_MCTRL); writel(val | ISMT_MCTRL_SS, priv->smba + ISMT_MSTR_MCTRL); } /** * ismt_process_desc() - handle the completion of the descriptor * @desc: the iSMT hardware descriptor * @data: data buffer from the upper layer * @priv: ismt_priv struct holding our dma buffer * @size: SMBus transaction type * @read_write: flag to indicate if this is a read or write */ static int ismt_process_desc(const struct ismt_desc *desc, union i2c_smbus_data *data, struct ismt_priv *priv, int size, char read_write) { u8 *dma_buffer = priv->dma_buffer; dev_dbg(&priv->pci_dev->dev, "Processing completed descriptor\n"); __ismt_desc_dump(&priv->pci_dev->dev, desc); if (desc->status & ISMT_DESC_SCS) { if (read_write == I2C_SMBUS_WRITE && size != I2C_SMBUS_PROC_CALL) return 0; switch (size) { case I2C_SMBUS_BYTE: case I2C_SMBUS_BYTE_DATA: data->byte = dma_buffer[0]; break; case I2C_SMBUS_WORD_DATA: case I2C_SMBUS_PROC_CALL: data->word = dma_buffer[0] | (dma_buffer[1] << 8); break; case I2C_SMBUS_BLOCK_DATA: case I2C_SMBUS_I2C_BLOCK_DATA: memcpy(&data->block[1], dma_buffer, desc->rxbytes); data->block[0] = desc->rxbytes; break; } return 0; } if (likely(desc->status & ISMT_DESC_NAK)) return -ENXIO; if (desc->status & ISMT_DESC_CRC) return -EBADMSG; if (desc->status & ISMT_DESC_COL) return -EAGAIN; if (desc->status & ISMT_DESC_LPR) return -EPROTO; if (desc->status & (ISMT_DESC_DLTO | ISMT_DESC_CLTO)) return -ETIMEDOUT; return -EIO; } /** * ismt_access() - process an SMBus command * @adap: the i2c host adapter * @addr: address of the i2c/SMBus target * @flags: command options * @read_write: read from or write to device * @command: the i2c/SMBus command to issue * @size: SMBus transaction type * @data: read/write data buffer */ static int ismt_access(struct i2c_adapter *adap, u16 addr, unsigned short flags, char read_write, u8 command, int size, union i2c_smbus_data *data) { int ret; unsigned long time_left; dma_addr_t dma_addr = 0; /* address of the data buffer */ u8 dma_size = 0; enum dma_data_direction dma_direction = 0; struct ismt_desc *desc; struct ismt_priv *priv = i2c_get_adapdata(adap); struct device *dev = &priv->pci_dev->dev; desc = &priv->hw[priv->head]; /* Initialize the DMA buffer */ memset(priv->dma_buffer, 0, sizeof(priv->dma_buffer)); /* Initialize the descriptor */ memset(desc, 0, sizeof(struct ismt_desc)); desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, read_write); /* Initialize common control bits */ if (likely(priv->using_msi)) desc->control = ISMT_DESC_INT | ISMT_DESC_FAIR; else desc->control = ISMT_DESC_FAIR; if ((flags & I2C_CLIENT_PEC) && (size != I2C_SMBUS_QUICK) && (size != I2C_SMBUS_I2C_BLOCK_DATA)) desc->control |= ISMT_DESC_PEC; switch (size) { case I2C_SMBUS_QUICK: dev_dbg(dev, "I2C_SMBUS_QUICK\n"); break; case I2C_SMBUS_BYTE: if (read_write == I2C_SMBUS_WRITE) { /* * Send Byte * The command field contains the write data */ dev_dbg(dev, "I2C_SMBUS_BYTE: WRITE\n"); desc->control |= ISMT_DESC_CWRL; desc->wr_len_cmd = command; } else { /* Receive Byte */ dev_dbg(dev, "I2C_SMBUS_BYTE: READ\n"); dma_size = 1; dma_direction = DMA_FROM_DEVICE; desc->rd_len = 1; } break; case I2C_SMBUS_BYTE_DATA: if (read_write == I2C_SMBUS_WRITE) { /* * Write Byte * Command plus 1 data byte */ dev_dbg(dev, "I2C_SMBUS_BYTE_DATA: WRITE\n"); desc->wr_len_cmd = 2; dma_size = 2; dma_direction = DMA_TO_DEVICE; priv->dma_buffer[0] = command; priv->dma_buffer[1] = data->byte; } else { /* Read Byte */ dev_dbg(dev, "I2C_SMBUS_BYTE_DATA: READ\n"); desc->control |= ISMT_DESC_CWRL; desc->wr_len_cmd = command; desc->rd_len = 1; dma_size = 1; dma_direction = DMA_FROM_DEVICE; } break; case I2C_SMBUS_WORD_DATA: if (read_write == I2C_SMBUS_WRITE) { /* Write Word */ dev_dbg(dev, "I2C_SMBUS_WORD_DATA: WRITE\n"); desc->wr_len_cmd = 3; dma_size = 3; dma_direction = DMA_TO_DEVICE; priv->dma_buffer[0] = command; priv->dma_buffer[1] = data->word & 0xff; priv->dma_buffer[2] = data->word >> 8; } else { /* Read Word */ dev_dbg(dev, "I2C_SMBUS_WORD_DATA: READ\n"); desc->wr_len_cmd = command; desc->control |= ISMT_DESC_CWRL; desc->rd_len = 2; dma_size = 2; dma_direction = DMA_FROM_DEVICE; } break; case I2C_SMBUS_PROC_CALL: dev_dbg(dev, "I2C_SMBUS_PROC_CALL\n"); desc->wr_len_cmd = 3; desc->rd_len = 2; dma_size = 3; dma_direction = DMA_BIDIRECTIONAL; priv->dma_buffer[0] = command; priv->dma_buffer[1] = data->word & 0xff; priv->dma_buffer[2] = data->word >> 8; break; case I2C_SMBUS_BLOCK_DATA: if (read_write == I2C_SMBUS_WRITE) { /* Block Write */ dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: WRITE\n"); dma_size = data->block[0] + 1; dma_direction = DMA_TO_DEVICE; desc->wr_len_cmd = dma_size; desc->control |= ISMT_DESC_BLK; priv->dma_buffer[0] = command; memcpy(&priv->dma_buffer[1], &data->block[1], dma_size - 1); } else { /* Block Read */ dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: READ\n"); dma_size = I2C_SMBUS_BLOCK_MAX; dma_direction = DMA_FROM_DEVICE; desc->rd_len = dma_size; desc->wr_len_cmd = command; desc->control |= (ISMT_DESC_BLK | ISMT_DESC_CWRL); } break; case I2C_SMBUS_I2C_BLOCK_DATA: /* Make sure the length is valid */ if (data->block[0] < 1) data->block[0] = 1; if (data->block[0] > I2C_SMBUS_BLOCK_MAX) data->block[0] = I2C_SMBUS_BLOCK_MAX; if (read_write == I2C_SMBUS_WRITE) { /* i2c Block Write */ dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: WRITE\n"); dma_size = data->block[0] + 1; dma_direction = DMA_TO_DEVICE; desc->wr_len_cmd = dma_size; desc->control |= ISMT_DESC_I2C; priv->dma_buffer[0] = command; memcpy(&priv->dma_buffer[1], &data->block[1], dma_size - 1); } else { /* i2c Block Read */ dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: READ\n"); dma_size = data->block[0]; dma_direction = DMA_FROM_DEVICE; desc->rd_len = dma_size; desc->wr_len_cmd = command; desc->control |= (ISMT_DESC_I2C | ISMT_DESC_CWRL); /* * Per the "Table 15-15. I2C Commands", * in the External Design Specification (EDS), * (Document Number: 508084, Revision: 2.0), * the _rw bit must be 0 */ desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, 0); } break; default: dev_err(dev, "Unsupported transaction %d\n", size); return -EOPNOTSUPP; } /* map the data buffer */ if (dma_size != 0) { dev_dbg(dev, " dev=%p\n", dev); dev_dbg(dev, " data=%p\n", data); dev_dbg(dev, " dma_buffer=%p\n", priv->dma_buffer); dev_dbg(dev, " dma_size=%d\n", dma_size); dev_dbg(dev, " dma_direction=%d\n", dma_direction); dma_addr = dma_map_single(dev, priv->dma_buffer, dma_size, dma_direction); if (dma_mapping_error(dev, dma_addr)) { dev_err(dev, "Error in mapping dma buffer %p\n", priv->dma_buffer); return -EIO; } dev_dbg(dev, " dma_addr = 0x%016llX\n", (unsigned long long)dma_addr); desc->dptr_low = lower_32_bits(dma_addr); desc->dptr_high = upper_32_bits(dma_addr); } reinit_completion(&priv->cmp); /* Add the descriptor */ ismt_submit_desc(priv); /* Now we wait for interrupt completion, 1s */ time_left = wait_for_completion_timeout(&priv->cmp, HZ*1); /* unmap the data buffer */ if (dma_size != 0) dma_unmap_single(&adap->dev, dma_addr, dma_size, dma_direction); if (unlikely(!time_left)) { dev_err(dev, "completion wait timed out\n"); ret = -ETIMEDOUT; goto out; } /* do any post processing of the descriptor here */ ret = ismt_process_desc(desc, data, priv, size, read_write); out: /* Update the ring pointer */ priv->head++; priv->head %= ISMT_DESC_ENTRIES; return ret; } /** * ismt_func() - report which i2c commands are supported by this adapter * @adap: the i2c host adapter */ static u32 ismt_func(struct i2c_adapter *adap) { return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_I2C_BLOCK | I2C_FUNC_SMBUS_PEC; } /** * smbus_algorithm - the adapter algorithm and supported functionality * @smbus_xfer: the adapter algorithm * @functionality: functionality supported by the adapter */ static const struct i2c_algorithm smbus_algorithm = { .smbus_xfer = ismt_access, .functionality = ismt_func, }; /** * ismt_handle_isr() - interrupt handler bottom half * @priv: iSMT private data */ static irqreturn_t ismt_handle_isr(struct ismt_priv *priv) { complete(&priv->cmp); return IRQ_HANDLED; } /** * ismt_do_interrupt() - IRQ interrupt handler * @vec: interrupt vector * @data: iSMT private data */ static irqreturn_t ismt_do_interrupt(int vec, void *data) { u32 val; struct ismt_priv *priv = data; /* * check to see it's our interrupt, return IRQ_NONE if not ours * since we are sharing interrupt */ val = readl(priv->smba + ISMT_MSTR_MSTS); if (!(val & (ISMT_MSTS_MIS | ISMT_MSTS_MEIS))) return IRQ_NONE; else writel(val | ISMT_MSTS_MIS | ISMT_MSTS_MEIS, priv->smba + ISMT_MSTR_MSTS); return ismt_handle_isr(priv); } /** * ismt_do_msi_interrupt() - MSI interrupt handler * @vec: interrupt vector * @data: iSMT private data */ static irqreturn_t ismt_do_msi_interrupt(int vec, void *data) { return ismt_handle_isr(data); } /** * ismt_hw_init() - initialize the iSMT hardware * @priv: iSMT private data */ static void ismt_hw_init(struct ismt_priv *priv) { u32 val; struct device *dev = &priv->pci_dev->dev; /* initialize the Master Descriptor Base Address (MDBA) */ writeq(priv->io_rng_dma, priv->smba + ISMT_MSTR_MDBA); /* initialize the Master Control Register (MCTRL) */ writel(ISMT_MCTRL_MEIE, priv->smba + ISMT_MSTR_MCTRL); /* initialize the Master Status Register (MSTS) */ writel(0, priv->smba + ISMT_MSTR_MSTS); /* initialize the Master Descriptor Size (MDS) */ val = readl(priv->smba + ISMT_MSTR_MDS); writel((val & ~ISMT_MDS_MASK) | (ISMT_DESC_ENTRIES - 1), priv->smba + ISMT_MSTR_MDS); /* * Set the SMBus speed (could use this for slow HW debuggers) */ val = readl(priv->smba + ISMT_SPGT); switch (bus_speed) { case 0: break; case 80: dev_dbg(dev, "Setting SMBus clock to 80 kHz\n"); writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_80K), priv->smba + ISMT_SPGT); break; case 100: dev_dbg(dev, "Setting SMBus clock to 100 kHz\n"); writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_100K), priv->smba + ISMT_SPGT); break; case 400: dev_dbg(dev, "Setting SMBus clock to 400 kHz\n"); writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_400K), priv->smba + ISMT_SPGT); break; case 1000: dev_dbg(dev, "Setting SMBus clock to 1000 kHz\n"); writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_1M), priv->smba + ISMT_SPGT); break; default: dev_warn(dev, "Invalid SMBus clock speed, only 0, 80, 100, 400, and 1000 are valid\n"); break; } val = readl(priv->smba + ISMT_SPGT); switch (val & ISMT_SPGT_SPD_MASK) { case ISMT_SPGT_SPD_80K: bus_speed = 80; break; case ISMT_SPGT_SPD_100K: bus_speed = 100; break; case ISMT_SPGT_SPD_400K: bus_speed = 400; break; case ISMT_SPGT_SPD_1M: bus_speed = 1000; break; } dev_dbg(dev, "SMBus clock is running at %d kHz\n", bus_speed); } /** * ismt_dev_init() - initialize the iSMT data structures * @priv: iSMT private data */ static int ismt_dev_init(struct ismt_priv *priv) { /* allocate memory for the descriptor */ priv->hw = dmam_alloc_coherent(&priv->pci_dev->dev, (ISMT_DESC_ENTRIES * sizeof(struct ismt_desc)), &priv->io_rng_dma, GFP_KERNEL); if (!priv->hw) return -ENOMEM; memset(priv->hw, 0, (ISMT_DESC_ENTRIES * sizeof(struct ismt_desc))); priv->head = 0; init_completion(&priv->cmp); return 0; } /** * ismt_int_init() - initialize interrupts * @priv: iSMT private data */ static int ismt_int_init(struct ismt_priv *priv) { int err; /* Try using MSI interrupts */ err = pci_enable_msi(priv->pci_dev); if (err) { dev_warn(&priv->pci_dev->dev, "Unable to use MSI interrupts, falling back to legacy\n"); goto intx; } err = devm_request_irq(&priv->pci_dev->dev, priv->pci_dev->irq, ismt_do_msi_interrupt, 0, "ismt-msi", priv); if (err) { pci_disable_msi(priv->pci_dev); goto intx; } priv->using_msi = true; goto done; /* Try using legacy interrupts */ intx: err = devm_request_irq(&priv->pci_dev->dev, priv->pci_dev->irq, ismt_do_interrupt, IRQF_SHARED, "ismt-intx", priv); if (err) { dev_err(&priv->pci_dev->dev, "no usable interrupts\n"); return -ENODEV; } priv->using_msi = false; done: return 0; } static struct pci_driver ismt_driver; /** * ismt_probe() - probe for iSMT devices * @pdev: PCI-Express device * @id: PCI-Express device ID */ static int ismt_probe(struct pci_dev *pdev, const struct pci_device_id *id) { int err; struct ismt_priv *priv; unsigned long start, len; priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; pci_set_drvdata(pdev, priv); i2c_set_adapdata(&priv->adapter, priv); priv->adapter.owner = THIS_MODULE; priv->adapter.class = I2C_CLASS_HWMON; priv->adapter.algo = &smbus_algorithm; /* set up the sysfs linkage to our parent device */ priv->adapter.dev.parent = &pdev->dev; /* number of retries on lost arbitration */ priv->adapter.retries = ISMT_MAX_RETRIES; priv->pci_dev = pdev; err = pcim_enable_device(pdev); if (err) { dev_err(&pdev->dev, "Failed to enable SMBus PCI device (%d)\n", err); return err; } /* enable bus mastering */ pci_set_master(pdev); /* Determine the address of the SMBus area */ start = pci_resource_start(pdev, SMBBAR); len = pci_resource_len(pdev, SMBBAR); if (!start || !len) { dev_err(&pdev->dev, "SMBus base address uninitialized, upgrade BIOS\n"); return -ENODEV; } snprintf(priv->adapter.name, sizeof(priv->adapter.name), "SMBus iSMT adapter at %lx", start); dev_dbg(&priv->pci_dev->dev, " start=0x%lX\n", start); dev_dbg(&priv->pci_dev->dev, " len=0x%lX\n", len); err = acpi_check_resource_conflict(&pdev->resource[SMBBAR]); if (err) { dev_err(&pdev->dev, "ACPI resource conflict!\n"); return err; } err = pci_request_region(pdev, SMBBAR, ismt_driver.name); if (err) { dev_err(&pdev->dev, "Failed to request SMBus region 0x%lx-0x%lx\n", start, start + len); return err; } priv->smba = pcim_iomap(pdev, SMBBAR, len); if (!priv->smba) { dev_err(&pdev->dev, "Unable to ioremap SMBus BAR\n"); return -ENODEV; } if ((pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) != 0) || (pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64)) != 0)) { if ((pci_set_dma_mask(pdev, DMA_BIT_MASK(32)) != 0) || (pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32)) != 0)) { dev_err(&pdev->dev, "pci_set_dma_mask fail %p\n", pdev); return -ENODEV; } } err = ismt_dev_init(priv); if (err) return err; ismt_hw_init(priv); err = ismt_int_init(priv); if (err) return err; err = i2c_add_adapter(&priv->adapter); if (err) { dev_err(&pdev->dev, "Failed to add SMBus iSMT adapter\n"); return -ENODEV; } return 0; } /** * ismt_remove() - release driver resources * @pdev: PCI-Express device */ static void ismt_remove(struct pci_dev *pdev) { struct ismt_priv *priv = pci_get_drvdata(pdev); i2c_del_adapter(&priv->adapter); } static struct pci_driver ismt_driver = { .name = "ismt_smbus", .id_table = ismt_ids, .probe = ismt_probe, .remove = ismt_remove, }; module_pci_driver(ismt_driver); MODULE_LICENSE("Dual BSD/GPL"); MODULE_AUTHOR("Bill E. Brown "); MODULE_DESCRIPTION("Intel SMBus Message Transport (iSMT) driver");