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-rw-r--r--hw/i2c/pm_smbus.c497
1 files changed, 497 insertions, 0 deletions
diff --git a/hw/i2c/pm_smbus.c b/hw/i2c/pm_smbus.c
new file mode 100644
index 000000000..d7eae548c
--- /dev/null
+++ b/hw/i2c/pm_smbus.c
@@ -0,0 +1,497 @@
+/*
+ * 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 2.1 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 "qemu/osdep.h"
+#include "hw/boards.h"
+#include "hw/i2c/pm_smbus.h"
+#include "hw/i2c/smbus_master.h"
+#include "migration/vmstate.h"
+
+#define SMBHSTSTS 0x00
+#define SMBHSTCNT 0x02
+#define SMBHSTCMD 0x03
+#define SMBHSTADD 0x04
+#define SMBHSTDAT0 0x05
+#define SMBHSTDAT1 0x06
+#define SMBBLKDAT 0x07
+#define SMBAUXCTL 0x0d
+
+#define STS_HOST_BUSY (1 << 0)
+#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 CTL_INTREN (1 << 0)
+#define CTL_KILL (1 << 1)
+#define CTL_LAST_BYTE (1 << 5)
+#define CTL_START (1 << 6)
+#define CTL_PEC_EN (1 << 7)
+#define CTL_RETURN_MASK 0x1f
+
+#define PROT_QUICK 0
+#define PROT_BYTE 1
+#define PROT_BYTE_DATA 2
+#define PROT_WORD_DATA 3
+#define PROT_PROC_CALL 4
+#define PROT_BLOCK_DATA 5
+#define PROT_I2C_BLOCK_READ 6
+
+#define AUX_PEC (1 << 0)
+#define AUX_BLK (1 << 1)
+#define AUX_MASK 0x3
+
+/*#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 PROT_QUICK:
+ ret = smbus_quick_command(bus, addr, read);
+ goto done;
+ case PROT_BYTE:
+ if (read) {
+ ret = smbus_receive_byte(bus, addr);
+ goto data8;
+ } else {
+ ret = smbus_send_byte(bus, addr, cmd);
+ goto done;
+ }
+ case PROT_BYTE_DATA:
+ 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 PROT_WORD_DATA:
+ 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 PROT_I2C_BLOCK_READ:
+ /* According to the Linux i2c-i801 driver:
+ * NB: page 240 of ICH5 datasheet shows that the R/#W
+ * bit should be cleared here, even when reading.
+ * However if SPD Write Disable is set (Lynx Point and later),
+ * the read will fail if we don't set the R/#W bit.
+ * So at least Linux may or may not set the read bit here.
+ * So just ignore the read bit for this command.
+ */
+ if (i2c_start_send(bus, addr)) {
+ goto error;
+ }
+ ret = i2c_send(bus, s->smb_data1);
+ if (ret) {
+ goto error;
+ }
+ if (i2c_start_recv(bus, addr)) {
+ goto error;
+ }
+ s->in_i2c_block_read = true;
+ s->smb_blkdata = i2c_recv(s->smbus);
+ s->op_done = false;
+ s->smb_stat |= STS_HOST_BUSY | STS_BYTE_DONE;
+ goto out;
+
+ case PROT_BLOCK_DATA:
+ if (read) {
+ ret = smbus_read_block(bus, addr, cmd, s->smb_data,
+ sizeof(s->smb_data), !s->i2c_enable,
+ !s->i2c_enable);
+ if (ret < 0) {
+ goto error;
+ }
+ s->smb_index = 0;
+ s->op_done = false;
+ if (s->smb_auxctl & AUX_BLK) {
+ s->smb_stat |= STS_INTR;
+ } else {
+ s->smb_blkdata = s->smb_data[0];
+ s->smb_stat |= STS_HOST_BUSY | STS_BYTE_DONE;
+ }
+ s->smb_data0 = ret;
+ goto out;
+ } else {
+ if (s->smb_auxctl & AUX_BLK) {
+ if (s->smb_index != s->smb_data0) {
+ s->smb_index = 0;
+ goto error;
+ }
+ /* Data is already all written to the queue, just do
+ the operation. */
+ s->smb_index = 0;
+ ret = smbus_write_block(bus, addr, cmd, s->smb_data,
+ s->smb_data0, !s->i2c_enable);
+ if (ret < 0) {
+ goto error;
+ }
+ s->op_done = true;
+ s->smb_stat |= STS_INTR;
+ s->smb_stat &= ~STS_HOST_BUSY;
+ } else {
+ s->op_done = false;
+ s->smb_stat |= STS_HOST_BUSY | STS_BYTE_DONE;
+ s->smb_data[0] = s->smb_blkdata;
+ s->smb_index = 0;
+ }
+ goto out;
+ }
+ 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_INTR;
+out:
+ return;
+
+error:
+ s->smb_stat |= STS_DEV_ERR;
+ return;
+}
+
+static void smb_transaction_start(PMSMBus *s)
+{
+ if (s->smb_ctl & CTL_INTREN) {
+ smb_transaction(s);
+ s->start_transaction_on_status_read = false;
+ } else {
+ /* Do not execute immediately the command; it will be
+ * executed when guest will read SMB_STAT register. This
+ * is to work around a bug in AMIBIOS (that is working
+ * around another bug in some specific hardware) where
+ * it waits for STS_HOST_BUSY to be set before waiting
+ * checking for status. If STS_HOST_BUSY doesn't get
+ * set, it gets stuck. */
+ s->smb_stat |= STS_HOST_BUSY;
+ s->start_transaction_on_status_read = true;
+ }
+}
+
+static bool
+smb_irq_value(PMSMBus *s)
+{
+ return ((s->smb_stat & ~STS_HOST_BUSY) != 0) && (s->smb_ctl & CTL_INTREN);
+}
+
+static bool
+smb_byte_by_byte(PMSMBus *s)
+{
+ if (s->op_done) {
+ return false;
+ }
+ if (s->in_i2c_block_read) {
+ return true;
+ }
+ return !(s->smb_auxctl & AUX_BLK);
+}
+
+static void smb_ioport_writeb(void *opaque, hwaddr addr, uint64_t val,
+ unsigned width)
+{
+ PMSMBus *s = opaque;
+ uint8_t clear_byte_done;
+
+ SMBUS_DPRINTF("SMB writeb port=0x%04" HWADDR_PRIx
+ " val=0x%02" PRIx64 "\n", addr, val);
+ switch(addr) {
+ case SMBHSTSTS:
+ clear_byte_done = s->smb_stat & val & STS_BYTE_DONE;
+ s->smb_stat &= ~(val & ~STS_HOST_BUSY);
+ if (clear_byte_done && smb_byte_by_byte(s)) {
+ uint8_t read = s->smb_addr & 0x01;
+
+ if (s->in_i2c_block_read) {
+ /* See comment below PROT_I2C_BLOCK_READ above. */
+ read = 1;
+ }
+
+ s->smb_index++;
+ if (s->smb_index >= PM_SMBUS_MAX_MSG_SIZE) {
+ s->smb_index = 0;
+ }
+ if (!read && s->smb_index == s->smb_data0) {
+ uint8_t prot = (s->smb_ctl >> 2) & 0x07;
+ uint8_t cmd = s->smb_cmd;
+ uint8_t addr = s->smb_addr >> 1;
+ int ret;
+
+ if (prot == PROT_I2C_BLOCK_READ) {
+ s->smb_stat |= STS_DEV_ERR;
+ goto out;
+ }
+
+ ret = smbus_write_block(s->smbus, addr, cmd, s->smb_data,
+ s->smb_data0, !s->i2c_enable);
+ if (ret < 0) {
+ s->smb_stat |= STS_DEV_ERR;
+ goto out;
+ }
+ s->op_done = true;
+ s->smb_stat |= STS_INTR;
+ s->smb_stat &= ~STS_HOST_BUSY;
+ } else if (!read) {
+ s->smb_data[s->smb_index] = s->smb_blkdata;
+ s->smb_stat |= STS_BYTE_DONE;
+ } else if (s->smb_ctl & CTL_LAST_BYTE) {
+ s->op_done = true;
+ if (s->in_i2c_block_read) {
+ s->in_i2c_block_read = false;
+ s->smb_blkdata = i2c_recv(s->smbus);
+ i2c_nack(s->smbus);
+ i2c_end_transfer(s->smbus);
+ } else {
+ s->smb_blkdata = s->smb_data[s->smb_index];
+ }
+ s->smb_index = 0;
+ s->smb_stat |= STS_INTR;
+ s->smb_stat &= ~STS_HOST_BUSY;
+ } else {
+ if (s->in_i2c_block_read) {
+ s->smb_blkdata = i2c_recv(s->smbus);
+ } else {
+ s->smb_blkdata = s->smb_data[s->smb_index];
+ }
+ s->smb_stat |= STS_BYTE_DONE;
+ }
+ }
+ break;
+ case SMBHSTCNT:
+ s->smb_ctl = val & ~CTL_START; /* CTL_START always reads 0 */
+ if (val & CTL_START) {
+ if (!s->op_done) {
+ s->smb_index = 0;
+ s->op_done = true;
+ if (s->in_i2c_block_read) {
+ s->in_i2c_block_read = false;
+ i2c_end_transfer(s->smbus);
+ }
+ }
+ smb_transaction_start(s);
+ }
+ if (s->smb_ctl & CTL_KILL) {
+ s->op_done = true;
+ s->smb_index = 0;
+ s->smb_stat |= STS_FAILED;
+ s->smb_stat &= ~STS_HOST_BUSY;
+ }
+ 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:
+ if (s->smb_index >= PM_SMBUS_MAX_MSG_SIZE) {
+ s->smb_index = 0;
+ }
+ if (s->smb_auxctl & AUX_BLK) {
+ s->smb_data[s->smb_index++] = val;
+ } else {
+ s->smb_blkdata = val;
+ }
+ break;
+ case SMBAUXCTL:
+ s->smb_auxctl = val & AUX_MASK;
+ break;
+ default:
+ break;
+ }
+
+ out:
+ if (s->set_irq) {
+ s->set_irq(s, smb_irq_value(s));
+ }
+}
+
+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;
+ if (s->start_transaction_on_status_read) {
+ /* execute command now */
+ s->start_transaction_on_status_read = false;
+ s->smb_stat &= ~STS_HOST_BUSY;
+ smb_transaction(s);
+ }
+ break;
+ case SMBHSTCNT:
+ val = s->smb_ctl & CTL_RETURN_MASK;
+ 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:
+ if (s->smb_auxctl & AUX_BLK && !s->in_i2c_block_read) {
+ if (s->smb_index >= PM_SMBUS_MAX_MSG_SIZE) {
+ s->smb_index = 0;
+ }
+ val = s->smb_data[s->smb_index++];
+ if (!s->op_done && s->smb_index == s->smb_data0) {
+ s->op_done = true;
+ s->smb_index = 0;
+ s->smb_stat &= ~STS_HOST_BUSY;
+ }
+ } else {
+ val = s->smb_blkdata;
+ }
+ break;
+ case SMBAUXCTL:
+ val = s->smb_auxctl;
+ break;
+ default:
+ val = 0;
+ break;
+ }
+ SMBUS_DPRINTF("SMB readb port=0x%04" HWADDR_PRIx " val=0x%02x\n",
+ addr, val);
+
+ if (s->set_irq) {
+ s->set_irq(s, smb_irq_value(s));
+ }
+
+ return val;
+}
+
+static void pm_smbus_reset(PMSMBus *s)
+{
+ s->op_done = true;
+ s->smb_index = 0;
+ s->smb_stat = 0;
+}
+
+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,
+};
+
+bool pm_smbus_vmstate_needed(void)
+{
+ MachineClass *mc = MACHINE_GET_CLASS(qdev_get_machine());
+
+ return !mc->smbus_no_migration_support;
+}
+
+const VMStateDescription pmsmb_vmstate = {
+ .name = "pmsmb",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT8(smb_stat, PMSMBus),
+ VMSTATE_UINT8(smb_ctl, PMSMBus),
+ VMSTATE_UINT8(smb_cmd, PMSMBus),
+ VMSTATE_UINT8(smb_addr, PMSMBus),
+ VMSTATE_UINT8(smb_data0, PMSMBus),
+ VMSTATE_UINT8(smb_data1, PMSMBus),
+ VMSTATE_UINT32(smb_index, PMSMBus),
+ VMSTATE_UINT8_ARRAY(smb_data, PMSMBus, PM_SMBUS_MAX_MSG_SIZE),
+ VMSTATE_UINT8(smb_auxctl, PMSMBus),
+ VMSTATE_UINT8(smb_blkdata, PMSMBus),
+ VMSTATE_BOOL(i2c_enable, PMSMBus),
+ VMSTATE_BOOL(op_done, PMSMBus),
+ VMSTATE_BOOL(in_i2c_block_read, PMSMBus),
+ VMSTATE_BOOL(start_transaction_on_status_read, PMSMBus),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+void pm_smbus_init(DeviceState *parent, PMSMBus *smb, bool force_aux_blk)
+{
+ smb->op_done = true;
+ smb->reset = pm_smbus_reset;
+ smb->smbus = i2c_init_bus(parent, "i2c");
+ if (force_aux_blk) {
+ smb->smb_auxctl |= AUX_BLK;
+ }
+ memory_region_init_io(&smb->io, OBJECT(parent), &pm_smbus_ops, smb,
+ "pm-smbus", 64);
+}