> -----Original Message----- > From: [email protected] [mailto:linux-i2c- > [email protected]] On Behalf Of Bill E Brown > Sent: Thursday, December 06, 2012 5:37 PM > To: Wolfram Sang > Cc: Jean Delvare; Heasley, Seth; [email protected]; Brown, Bill E > Subject: [PATCH v4] i2c: Adding support for Intel iSMT SMBus 2.0 host > controller > > From: Bill Brown <[email protected]> > > The iSMT (Intel SMBus Message Transport) supports multi-master > I2C/SMBus, as well as IPMI. It's operation is DMA-based and utilizes > descriptors to initiate transactions on the bus. > > The iSMT hardware can act as both a master and a target, although this driver > only supports being a master. >
Forgot to run checkpatch on v3, please use v4. Bill > Signed-off-by: Bill Brown <[email protected]> > --- > Documentation/i2c/busses/i2c-ismt | 36 ++ > drivers/i2c/busses/Kconfig | 10 + > drivers/i2c/busses/Makefile | 1 + > drivers/i2c/busses/i2c-ismt.c | 911 > +++++++++++++++++++++++++++++++++++++ > 4 files changed, 958 insertions(+), 0 deletions(-) create mode 100644 > Documentation/i2c/busses/i2c-ismt create mode 100644 > drivers/i2c/busses/i2c-ismt.c > > diff --git a/Documentation/i2c/busses/i2c-ismt > b/Documentation/i2c/busses/i2c-ismt > new file mode 100644 > index 0000000..ed6375c > --- /dev/null > +++ b/Documentation/i2c/busses/i2c-ismt > @@ -0,0 +1,36 @@ > +Kernel driver i2c-ismt > + > +Supported adapters: > + * Intel S12xx series SOCs > + > +Authors: > + Bill Brown <[email protected]> > + > + > +Module Parameters > +----------------- > + > +* bus_speed (unsigned int) > +Allows changing of the bus speed. Normally, the bus speed is set by > +the BIOS and never needs to be changed. However, some SMBus analyzers > +are too slow for monitoring the bus during debug, thus the need for this > module parameter. > +Available bus frequency settings: > + 0 no change > + 1 80 kHz > + 2 100 kHz > + 3 400 kHz > + 4 1 MHz > + > + > +Description > +----------- > + > +The S12xx series of SOCs have a pair of integrated SMBus 2.0 > +controllers targeted primarily at the microserver and storage markets. > + > +The S12xx series contain a pair of PCI functions. An output of lspci > +will show something similar to the following: > + > + 00:13.0 System peripheral: Intel Corporation Device 0xc59 > + 00:13.1 System peripheral: Intel Corporation Device 0xc5a > + > diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index > 7244c8b..64d5756 100644 > --- a/drivers/i2c/busses/Kconfig > +++ b/drivers/i2c/busses/Kconfig > @@ -119,6 +119,16 @@ config I2C_ISCH > This driver can also be built as a module. If so, the module > will be called i2c-isch. > > +config I2C_ISMT > + tristate "Intel iSMT SMBus Controller" > + depends on PCI > + help > + If you say yes to this option, support will be included for the Intel > + iSMT SMBus host controller interface. > + > + This driver can also be built as a module. If so, the module will be > + called i2c-ismt. > + > config I2C_PIIX4 > tristate "Intel PIIX4 and compatible > (ATI/AMD/Serverworks/Broadcom/SMSC)" > depends on PCI > diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index > ce3c2be..527a1f1 100644 > --- a/drivers/i2c/busses/Makefile > +++ b/drivers/i2c/busses/Makefile > @@ -14,6 +14,7 @@ obj-$(CONFIG_I2C_AMD756_S4882) += i2c- > amd756-s4882.o > obj-$(CONFIG_I2C_AMD8111) += i2c-amd8111.o > obj-$(CONFIG_I2C_I801) += i2c-i801.o > obj-$(CONFIG_I2C_ISCH) += i2c-isch.o > +obj-$(CONFIG_I2C_ISMT) += i2c-ismt.o > obj-$(CONFIG_I2C_NFORCE2) += i2c-nforce2.o > obj-$(CONFIG_I2C_NFORCE2_S4985) += i2c-nforce2-s4985.o > obj-$(CONFIG_I2C_PIIX4) += i2c-piix4.o > diff --git a/drivers/i2c/busses/i2c-ismt.c b/drivers/i2c/busses/i2c-ismt.c new > file mode 100644 index 0000000..17b1bdd > --- /dev/null > +++ b/drivers/i2c/busses/i2c-ismt.c > @@ -0,0 +1,911 @@ > +/* > + * 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. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the Free Software > + * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. > + * 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 <linux/module.h> > +#include <linux/init.h> > +#include <linux/pci.h> > +#include <linux/kernel.h> > +#include <linux/stddef.h> > +#include <linux/completion.h> > +#include <linux/dma-mapping.h> > +#include <linux/i2c.h> > +#include <linux/acpi.h> > +#include <linux/interrupt.h> > + > +/* PCI Address Constants */ > +#define SMBBAR 0 > + > +/* PCI DIDs for the Intel SMBus Message Transport (SMT) Devices */ > +#define PCI_DEVICE_ID_INTEL_S1200_SMB_SMT0 0x0c59 > +#define PCI_DEVICE_ID_INTEL_S1200_SMB_SMT1 0x0c5a > + > +#define ISMT_DESC_ENTRIES 32 /* 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 + <addr>) */ > +#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 *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 + 3]; /* temp R/W data > buffer */ > + bool using_msi; /* type of interrupt > flag */ > +}; > + > +/** > + * ismt_ids - PCI device IDs supported by this driver */ static const > +DEFINE_PCI_DEVICE_TABLE(ismt_ids) = { > + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, > PCI_DEVICE_ID_INTEL_S1200_SMB_SMT0) }, > + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, > PCI_DEVICE_ID_INTEL_S1200_SMB_SMT1) }, > + { 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"); > + > +#if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG) > +/** > + * 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); > + 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_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%016lX\n", > + priv->smba + ISMT_GR_SMTICL, > + 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%016lX\n", > + priv->smba + ISMT_MSTR_MDBA, > + 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)); > +} > +#endif > + > +/** > + * 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 > + * @dma_buffer: temporary buffer for the DMA engine > + * @size: SMBus transaction type > + */ > +static int ismt_process_desc(const struct ismt_desc *desc, > + union i2c_smbus_data *data, > + u8 *dma_buffer, int size) > +{ > + if (likely(desc->status & ISMT_DESC_SCS)) { > + if (size != I2C_SMBUS_QUICK) > + memcpy(data, dma_buffer, sizeof(*data)); > + 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; > + 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 descriptor */ > + memset(desc, 0, sizeof(struct ismt_desc)); > + desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, read_write); > + > + /* Create a temporary buffer for the DMA transaction */ > + /* and insert the command at the beginning of the buffer */ > + if (size != I2C_SMBUS_QUICK) { > + memcpy(priv->dma_buffer + 1, data, sizeof(*data)); > + priv->dma_buffer[0] = command; > + } > + > + /* 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; > + } 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; > + } 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; > + 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; > + } 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; > + > + 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(&priv->pci_dev->dev, > + priv->dma_buffer, > + dma_size, > + dma_direction); > + > + dev_dbg(dev, " dma_addr = 0x%016llX\n", > + dma_addr); > + > + desc->dptr_low = lower_32_bits(dma_addr); > + desc->dptr_high = upper_32_bits(dma_addr); > + } > + > + INIT_COMPLETION(priv->cmp); > + > + /* Add the descriptor */ > + ismt_submit_desc(priv); > + > + /* Now we wait for interrupt completion, 1s */ > + ret = wait_for_completion_interruptible_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 (likely(ret > 0)) > + /* do any post processing of the descriptor here */ > + ret = ismt_process_desc(desc, data, priv->dma_buffer, size); > + else if (ret == 0) { > + dev_err(dev, "completion wait timed out\n"); > + ret = -ETIMEDOUT; > + } else { > + dev_err(dev, "completion wait interrupted\n"); > + ret = -EIO; > + } > + > + /* 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_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 __devinit ismt_hw_init(struct ismt_priv *priv) { > + u32 val; > + struct device *dev = &priv->pci_dev->dev; > + > + /* initialize the Master Descriptor Base Address (MDBA) */ > + writel(priv->io_rng_dma, priv->smba + ISMT_MSTR_MDBA); > + writel(priv->io_rng_dma >> 32, priv->smba + ISMT_MSTR_MDBA + > 4); > + > + /* 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 1: > + dev_dbg(dev, "Setting SMBus clock to 80kHz\n"); > + writel(((val & ~ISMT_SPGT_SPD_MASK) | > ISMT_SPGT_SPD_80K), > + priv->smba + ISMT_SPGT); > + break; > + > + case 2: > + dev_dbg(dev, "Setting SMBus clock to 100kHz\n"); > + writel(((val & ~ISMT_SPGT_SPD_MASK) | > ISMT_SPGT_SPD_100K), > + priv->smba + ISMT_SPGT); > + break; > + > + case 3: > + dev_dbg(dev, "Setting SMBus clock to 400kHz\n"); > + writel(((val & ~ISMT_SPGT_SPD_MASK) | > ISMT_SPGT_SPD_400K), > + priv->smba + ISMT_SPGT); > + break; > + > + case 4: > + dev_dbg(dev, "Setting SMBus clock to 1MHz\n"); > + writel(((val & ~ISMT_SPGT_SPD_MASK) | > ISMT_SPGT_SPD_1M), > + priv->smba + ISMT_SPGT); > + break; > + > + default: > + dev_dbg(dev, "Invalid SMBus clock speed, only 1-4 are > valid\n"); > + break; > + } > +} > + > +/** > + * ismt_dev_init() - initialize the iSMT data structures > + * @priv: iSMT private data > + */ > +static int __devinit 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 __devinit 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"); > + 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 __devinit > +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"); > + err = -ENODEV; > + goto fail; > + } > + > + 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_warn(&pdev->dev, "pci_set_dma_mask fail > %p\n", > + pdev); > + goto fail; > + } > + } > + > + err = ismt_dev_init(priv); > + if (err) > + goto fail; > + > + ismt_hw_init(priv); > + > + err = ismt_int_init(priv); > + if (err) > + goto fail; > + > + err = i2c_add_adapter(&priv->adapter); > + if (err) { > + dev_err(&pdev->dev, "Failed to add SMBus iSMT > adapter\n"); > + err = -ENODEV; > + goto fail; > + } > + return 0; > + > +fail: > + pci_release_region(pdev, SMBBAR); > + return err; > +} > + > +/** > + * ismt_remove() - release driver resources > + * @pdev: PCI-Express device > + */ > +static void __devexit ismt_remove(struct pci_dev *pdev) { > + struct ismt_priv *priv = pci_get_drvdata(pdev); > + > + i2c_del_adapter(&priv->adapter); > + pci_release_region(pdev, SMBBAR); > +} > + > +/** > + * ismt_suspend() - place the device in suspend > + * @pdev: PCI-Express device > + * @mesg: PM message > + */ > +#ifdef CONFIG_PM > +static int ismt_suspend(struct pci_dev *pdev, pm_message_t mesg) { > + pci_save_state(pdev); > + pci_set_power_state(pdev, pci_choose_state(pdev, mesg)); > + return 0; > +} > + > +/** > + * ismt_resume() - PCI resume code > + * @pdev: PCI-Express device > + */ > +static int ismt_resume(struct pci_dev *pdev) { > + pci_set_power_state(pdev, PCI_D0); > + pci_restore_state(pdev); > + return pci_enable_device(pdev); > +} > + > +#else > + > +#define ismt_suspend NULL > +#define ismt_resume NULL > + > +#endif > + > +static struct pci_driver ismt_driver = { > + .name = "ismt_smbus", > + .id_table = ismt_ids, > + .probe = ismt_probe, > + .remove = __devexit_p(ismt_remove), > + .suspend = ismt_suspend, > + .resume = ismt_resume, > +}; > + > +module_pci_driver(ismt_driver); > + > +MODULE_LICENSE("Dual BSD/GPL"); > +MODULE_AUTHOR("Bill E. Brown <[email protected]>"); > +MODULE_DESCRIPTION("Intel SMBus Message Transport (iSMT) driver"); > -- > 1.6.2.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the > body > of a message to [email protected] More majordomo info at > http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
