/* * PC SMBus implementation * splitted from acpi.c * * Copyright (c) 2006 Fabrice Bellard * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License version 2 as published by the Free Software Foundation. * * This library 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, see * <http://www.gnu.org/licenses/>. */ #include "hw/hw.h" #include "hw/i386/pc.h" #include "hw/i2c/pm_smbus.h" #include "hw/i2c/smbus.h" /* no save/load? */ #define SMBHSTSTS 0x00 #define SMBHSTCNT 0x02 #define SMBHSTCMD 0x03 #define SMBHSTADD 0x04 #define SMBHSTDAT0 0x05 #define SMBHSTDAT1 0x06 #define SMBBLKDAT 0x07 #define STS_HOST_BUSY (1) #define STS_INTR (1<<1) #define STS_DEV_ERR (1<<2) #define STS_BUS_ERR (1<<3) #define STS_FAILED (1<<4) #define STS_SMBALERT (1<<5) #define STS_INUSE_STS (1<<6) #define STS_BYTE_DONE (1<<7) /* Signs of successfully transaction end : * ByteDoneStatus = 1 (STS_BYTE_DONE) and INTR = 1 (STS_INTR ) */ //#define DEBUG #ifdef DEBUG # define SMBUS_DPRINTF(format, ...) printf(format, ## __VA_ARGS__) #else # define SMBUS_DPRINTF(format, ...) do { } while (0) #endif static void smb_transaction(PMSMBus *s) { uint8_t prot = (s->smb_ctl >> 2) & 0x07; uint8_t read = s->smb_addr & 0x01; uint8_t cmd = s->smb_cmd; uint8_t addr = s->smb_addr >> 1; I2CBus *bus = s->smbus; int ret; SMBUS_DPRINTF("SMBus trans addr=0x%02x prot=0x%02x\n", addr, prot); /* Transaction isn't exec if STS_DEV_ERR bit set */ if ((s->smb_stat & STS_DEV_ERR) != 0) { goto error; } switch(prot) { case 0x0: ret = smbus_quick_command(bus, addr, read); goto done; case 0x1: if (read) { ret = smbus_receive_byte(bus, addr); goto data8; } else { ret = smbus_send_byte(bus, addr, cmd); goto done; } case 0x2: if (read) { ret = smbus_read_byte(bus, addr, cmd); goto data8; } else { ret = smbus_write_byte(bus, addr, cmd, s->smb_data0); goto done; } break; case 0x3: if (read) { ret = smbus_read_word(bus, addr, cmd); goto data16; } else { ret = smbus_write_word(bus, addr, cmd, (s->smb_data1 << 8) | s->smb_data0); goto done; } break; case 0x5: if (read) { ret = smbus_read_block(bus, addr, cmd, s->smb_data); goto data8; } else { ret = smbus_write_block(bus, addr, cmd, s->smb_data, s->smb_data0); goto done; } break; default: goto error; } abort(); data16: if (ret < 0) { goto error; } s->smb_data1 = ret >> 8; data8: if (ret < 0) { goto error; } s->smb_data0 = ret; done: if (ret < 0) { goto error; } s->smb_stat |= STS_BYTE_DONE | STS_INTR; return; error: s->smb_stat |= STS_DEV_ERR; return; } static void smb_ioport_writeb(void *opaque, hwaddr addr, uint64_t val, unsigned width) { PMSMBus *s = opaque; SMBUS_DPRINTF("SMB writeb port=0x%04" HWADDR_PRIx " val=0x%02" PRIx64 "\n", addr, val); switch(addr) { case SMBHSTSTS: s->smb_stat = (~(val & 0xff)) & s->smb_stat; s->smb_index = 0; break; case SMBHSTCNT: s->smb_ctl = val; if (val & 0x40) smb_transaction(s); break; case SMBHSTCMD: s->smb_cmd = val; break; case SMBHSTADD: s->smb_addr = val; break; case SMBHSTDAT0: s->smb_data0 = val; break; case SMBHSTDAT1: s->smb_data1 = val; break; case SMBBLKDAT: s->smb_data[s->smb_index++] = val; if (s->smb_index > 31) s->smb_index = 0; break; default: break; } } static uint64_t smb_ioport_readb(void *opaque, hwaddr addr, unsigned width) { PMSMBus *s = opaque; uint32_t val; switch(addr) { case SMBHSTSTS: val = s->smb_stat; break; case SMBHSTCNT: s->smb_index = 0; val = s->smb_ctl & 0x1f; break; case SMBHSTCMD: val = s->smb_cmd; break; case SMBHSTADD: val = s->smb_addr; break; case SMBHSTDAT0: val = s->smb_data0; break; case SMBHSTDAT1: val = s->smb_data1; break; case SMBBLKDAT: val = s->smb_data[s->smb_index++]; if (s->smb_index > 31) s->smb_index = 0; break; default: val = 0; break; } SMBUS_DPRINTF("SMB readb port=0x%04" HWADDR_PRIx " val=0x%02x\n", addr, val); return val; } static const MemoryRegionOps pm_smbus_ops = { .read = smb_ioport_readb, .write = smb_ioport_writeb, .valid.min_access_size = 1, .valid.max_access_size = 1, .endianness = DEVICE_LITTLE_ENDIAN, }; void pm_smbus_init(DeviceState *parent, PMSMBus *smb) { smb->smbus = i2c_init_bus(parent, "i2c"); memory_region_init_io(&smb->io, OBJECT(parent), &pm_smbus_ops, smb, "pm-smbus", 64); }