/* * ARM Aspeed I2C controller * * Copyright (C) 2016 IBM Corp. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * 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, see . * */ #include "qemu/osdep.h" #include "hw/sysbus.h" #include "migration/vmstate.h" #include "qemu/cutils.h" #include "qemu/log.h" #include "qemu/module.h" #include "qemu/error-report.h" #include "qapi/error.h" #include "hw/i2c/aspeed_i2c.h" #include "hw/irq.h" #include "hw/qdev-properties.h" #include "hw/registerfields.h" #include "trace.h" static inline void aspeed_i2c_bus_raise_interrupt(AspeedI2CBus *bus) { AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller); uint32_t reg_intr_sts = aspeed_i2c_bus_intr_sts_offset(bus); uint32_t intr_ctrl_reg = aspeed_i2c_bus_intr_ctrl_offset(bus); bool raise_irq; if (trace_event_get_state_backends(TRACE_ASPEED_I2C_BUS_RAISE_INTERRUPT)) { g_autofree char *buf = g_strdup_printf("%s%s%s%s%s%s", aspeed_i2c_bus_pkt_mode_en(bus) && ARRAY_FIELD_EX32(bus->regs, I2CM_INTR_STS, PKT_CMD_DONE) ? "pktdone|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_intr_sts, TX_NAK) ? "nak|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_intr_sts, TX_ACK) ? "ack|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_intr_sts, RX_DONE) ? "done|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_intr_sts, NORMAL_STOP) ? "normal|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_intr_sts, ABNORMAL) ? "abnormal" : ""); trace_aspeed_i2c_bus_raise_interrupt(bus->regs[reg_intr_sts], buf); } raise_irq = bus->regs[reg_intr_sts] & bus->regs[intr_ctrl_reg]; /* In packet mode we don't mask off INTR_STS */ if (!aspeed_i2c_bus_pkt_mode_en(bus)) { bus->regs[reg_intr_sts] &= bus->regs[intr_ctrl_reg]; } if (raise_irq) { bus->controller->intr_status |= 1 << bus->id; qemu_irq_raise(aic->bus_get_irq(bus)); } } static uint64_t aspeed_i2c_bus_old_read(AspeedI2CBus *bus, hwaddr offset, unsigned size) { AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller); uint64_t value = bus->regs[offset / sizeof(*bus->regs)]; switch (offset) { case A_I2CD_FUN_CTRL: case A_I2CD_AC_TIMING1: case A_I2CD_AC_TIMING2: case A_I2CD_INTR_CTRL: case A_I2CD_INTR_STS: case A_I2CD_DEV_ADDR: case A_I2CD_POOL_CTRL: case A_I2CD_BYTE_BUF: /* Value is already set, don't do anything. */ break; case A_I2CD_CMD: value = SHARED_FIELD_DP32(value, BUS_BUSY_STS, i2c_bus_busy(bus->bus)); break; case A_I2CD_DMA_ADDR: if (!aic->has_dma) { qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n", __func__); value = -1; } break; case A_I2CD_DMA_LEN: if (!aic->has_dma) { qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n", __func__); value = -1; } break; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, offset); value = -1; break; } trace_aspeed_i2c_bus_read(bus->id, offset, size, value); return value; } static uint64_t aspeed_i2c_bus_new_read(AspeedI2CBus *bus, hwaddr offset, unsigned size) { uint64_t value = bus->regs[offset / sizeof(*bus->regs)]; switch (offset) { case A_I2CC_FUN_CTRL: case A_I2CC_AC_TIMING: case A_I2CC_POOL_CTRL: case A_I2CM_INTR_CTRL: case A_I2CM_INTR_STS: case A_I2CC_MS_TXRX_BYTE_BUF: case A_I2CM_DMA_LEN: case A_I2CM_DMA_TX_ADDR: case A_I2CM_DMA_RX_ADDR: case A_I2CM_DMA_LEN_STS: case A_I2CC_DMA_ADDR: case A_I2CC_DMA_LEN: /* Value is already set, don't do anything. */ break; case A_I2CM_CMD: value = SHARED_FIELD_DP32(value, BUS_BUSY_STS, i2c_bus_busy(bus->bus)); break; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, offset); value = -1; break; } trace_aspeed_i2c_bus_read(bus->id, offset, size, value); return value; } static uint64_t aspeed_i2c_bus_read(void *opaque, hwaddr offset, unsigned size) { AspeedI2CBus *bus = opaque; if (aspeed_i2c_is_new_mode(bus->controller)) { return aspeed_i2c_bus_new_read(bus, offset, size); } return aspeed_i2c_bus_old_read(bus, offset, size); } static void aspeed_i2c_set_state(AspeedI2CBus *bus, uint8_t state) { if (aspeed_i2c_is_new_mode(bus->controller)) { SHARED_ARRAY_FIELD_DP32(bus->regs, R_I2CC_MS_TXRX_BYTE_BUF, TX_STATE, state); } else { SHARED_ARRAY_FIELD_DP32(bus->regs, R_I2CD_CMD, TX_STATE, state); } } static uint8_t aspeed_i2c_get_state(AspeedI2CBus *bus) { if (aspeed_i2c_is_new_mode(bus->controller)) { return SHARED_ARRAY_FIELD_EX32(bus->regs, R_I2CC_MS_TXRX_BYTE_BUF, TX_STATE); } return SHARED_ARRAY_FIELD_EX32(bus->regs, R_I2CD_CMD, TX_STATE); } static int aspeed_i2c_dma_read(AspeedI2CBus *bus, uint8_t *data) { MemTxResult result; AspeedI2CState *s = bus->controller; uint32_t reg_dma_addr = aspeed_i2c_bus_dma_addr_offset(bus); uint32_t reg_dma_len = aspeed_i2c_bus_dma_len_offset(bus); result = address_space_read(&s->dram_as, bus->regs[reg_dma_addr], MEMTXATTRS_UNSPECIFIED, data, 1); if (result != MEMTX_OK) { qemu_log_mask(LOG_GUEST_ERROR, "%s: DRAM read failed @%08x\n", __func__, bus->regs[reg_dma_addr]); return -1; } bus->regs[reg_dma_addr]++; bus->regs[reg_dma_len]--; return 0; } static int aspeed_i2c_bus_send(AspeedI2CBus *bus, uint8_t pool_start) { AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller); int ret = -1; int i; uint32_t reg_cmd = aspeed_i2c_bus_cmd_offset(bus); uint32_t reg_pool_ctrl = aspeed_i2c_bus_pool_ctrl_offset(bus); uint32_t reg_byte_buf = aspeed_i2c_bus_byte_buf_offset(bus); uint32_t reg_dma_len = aspeed_i2c_bus_dma_len_offset(bus); int pool_tx_count = SHARED_ARRAY_FIELD_EX32(bus->regs, reg_pool_ctrl, TX_COUNT); if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, TX_BUFF_EN)) { for (i = pool_start; i < pool_tx_count; i++) { uint8_t *pool_base = aic->bus_pool_base(bus); trace_aspeed_i2c_bus_send("BUF", i + 1, pool_tx_count, pool_base[i]); ret = i2c_send(bus->bus, pool_base[i]); if (ret) { break; } } SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, TX_BUFF_EN, 0); } else if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, TX_DMA_EN)) { /* In new mode, clear how many bytes we TXed */ if (aspeed_i2c_is_new_mode(bus->controller)) { ARRAY_FIELD_DP32(bus->regs, I2CM_DMA_LEN_STS, TX_LEN, 0); } while (bus->regs[reg_dma_len]) { uint8_t data; aspeed_i2c_dma_read(bus, &data); trace_aspeed_i2c_bus_send("DMA", bus->regs[reg_dma_len], bus->regs[reg_dma_len], data); ret = i2c_send(bus->bus, data); if (ret) { break; } /* In new mode, keep track of how many bytes we TXed */ if (aspeed_i2c_is_new_mode(bus->controller)) { ARRAY_FIELD_DP32(bus->regs, I2CM_DMA_LEN_STS, TX_LEN, ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN_STS, TX_LEN) + 1); } } SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, TX_DMA_EN, 0); } else { trace_aspeed_i2c_bus_send("BYTE", pool_start, 1, bus->regs[reg_byte_buf]); ret = i2c_send(bus->bus, bus->regs[reg_byte_buf]); } return ret; } static void aspeed_i2c_bus_recv(AspeedI2CBus *bus) { AspeedI2CState *s = bus->controller; AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s); uint8_t data; int i; uint32_t reg_cmd = aspeed_i2c_bus_cmd_offset(bus); uint32_t reg_pool_ctrl = aspeed_i2c_bus_pool_ctrl_offset(bus); uint32_t reg_byte_buf = aspeed_i2c_bus_byte_buf_offset(bus); uint32_t reg_dma_len = aspeed_i2c_bus_dma_len_offset(bus); uint32_t reg_dma_addr = aspeed_i2c_bus_dma_addr_offset(bus); int pool_rx_count = SHARED_ARRAY_FIELD_EX32(bus->regs, reg_pool_ctrl, RX_COUNT); if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, RX_BUFF_EN)) { uint8_t *pool_base = aic->bus_pool_base(bus); for (i = 0; i < pool_rx_count; i++) { pool_base[i] = i2c_recv(bus->bus); trace_aspeed_i2c_bus_recv("BUF", i + 1, pool_rx_count, pool_base[i]); } /* Update RX count */ SHARED_ARRAY_FIELD_DP32(bus->regs, reg_pool_ctrl, RX_COUNT, i & 0xff); SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, RX_BUFF_EN, 0); } else if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, RX_DMA_EN)) { uint8_t data; /* In new mode, clear how many bytes we RXed */ if (aspeed_i2c_is_new_mode(bus->controller)) { ARRAY_FIELD_DP32(bus->regs, I2CM_DMA_LEN_STS, RX_LEN, 0); } while (bus->regs[reg_dma_len]) { MemTxResult result; data = i2c_recv(bus->bus); trace_aspeed_i2c_bus_recv("DMA", bus->regs[reg_dma_len], bus->regs[reg_dma_len], data); result = address_space_write(&s->dram_as, bus->regs[reg_dma_addr], MEMTXATTRS_UNSPECIFIED, &data, 1); if (result != MEMTX_OK) { qemu_log_mask(LOG_GUEST_ERROR, "%s: DRAM write failed @%08x\n", __func__, bus->regs[reg_dma_addr]); return; } bus->regs[reg_dma_addr]++; bus->regs[reg_dma_len]--; /* In new mode, keep track of how many bytes we RXed */ if (aspeed_i2c_is_new_mode(bus->controller)) { ARRAY_FIELD_DP32(bus->regs, I2CM_DMA_LEN_STS, RX_LEN, ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN_STS, RX_LEN) + 1); } } SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, RX_DMA_EN, 0); } else { data = i2c_recv(bus->bus); trace_aspeed_i2c_bus_recv("BYTE", 1, 1, bus->regs[reg_byte_buf]); SHARED_ARRAY_FIELD_DP32(bus->regs, reg_byte_buf, RX_BUF, data); } } static void aspeed_i2c_handle_rx_cmd(AspeedI2CBus *bus) { uint32_t reg_cmd = aspeed_i2c_bus_cmd_offset(bus); uint32_t reg_intr_sts = aspeed_i2c_bus_intr_sts_offset(bus); aspeed_i2c_set_state(bus, I2CD_MRXD); aspeed_i2c_bus_recv(bus); SHARED_ARRAY_FIELD_DP32(bus->regs, reg_intr_sts, RX_DONE, 1); if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_S_RX_CMD_LAST)) { i2c_nack(bus->bus); } SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, M_RX_CMD, 0); SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, M_S_RX_CMD_LAST, 0); aspeed_i2c_set_state(bus, I2CD_MACTIVE); } static uint8_t aspeed_i2c_get_addr(AspeedI2CBus *bus) { AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller); uint32_t reg_byte_buf = aspeed_i2c_bus_byte_buf_offset(bus); uint32_t reg_cmd = aspeed_i2c_bus_cmd_offset(bus); if (aspeed_i2c_bus_pkt_mode_en(bus)) { return (ARRAY_FIELD_EX32(bus->regs, I2CM_CMD, PKT_DEV_ADDR) << 1) | SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_RX_CMD); } if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, TX_BUFF_EN)) { uint8_t *pool_base = aic->bus_pool_base(bus); return pool_base[0]; } else if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, TX_DMA_EN)) { uint8_t data; aspeed_i2c_dma_read(bus, &data); return data; } else { return bus->regs[reg_byte_buf]; } } static bool aspeed_i2c_check_sram(AspeedI2CBus *bus) { AspeedI2CState *s = bus->controller; AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s); uint32_t reg_cmd = aspeed_i2c_bus_cmd_offset(bus); bool dma_en = SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, RX_DMA_EN) || SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, TX_DMA_EN) || SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, RX_BUFF_EN) || SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, TX_BUFF_EN); if (!aic->check_sram) { return true; } /* * AST2500: SRAM must be enabled before using the Buffer Pool or * DMA mode. */ if (!FIELD_EX32(s->ctrl_global, I2C_CTRL_GLOBAL, SRAM_EN) && dma_en) { qemu_log_mask(LOG_GUEST_ERROR, "%s: SRAM is not enabled\n", __func__); return false; } return true; } static void aspeed_i2c_bus_cmd_dump(AspeedI2CBus *bus) { g_autofree char *cmd_flags = NULL; uint32_t count; uint32_t reg_cmd = aspeed_i2c_bus_cmd_offset(bus); uint32_t reg_pool_ctrl = aspeed_i2c_bus_pool_ctrl_offset(bus); uint32_t reg_intr_sts = aspeed_i2c_bus_intr_sts_offset(bus); uint32_t reg_dma_len = aspeed_i2c_bus_dma_len_offset(bus); if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, RX_BUFF_EN)) { count = SHARED_ARRAY_FIELD_EX32(bus->regs, reg_pool_ctrl, TX_COUNT); } else if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, RX_DMA_EN)) { count = bus->regs[reg_dma_len]; } else { /* BYTE mode */ count = 1; } cmd_flags = g_strdup_printf("%s%s%s%s%s%s%s%s%s", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_START_CMD) ? "start|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, RX_DMA_EN) ? "rxdma|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, TX_DMA_EN) ? "txdma|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, RX_BUFF_EN) ? "rxbuf|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, TX_BUFF_EN) ? "txbuf|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_TX_CMD) ? "tx|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_RX_CMD) ? "rx|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_S_RX_CMD_LAST) ? "last|" : "", SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_STOP_CMD) ? "stop|" : ""); trace_aspeed_i2c_bus_cmd(bus->regs[reg_cmd], cmd_flags, count, bus->regs[reg_intr_sts]); } /* * The state machine needs some refinement. It is only used to track * invalid STOP commands for the moment. */ static void aspeed_i2c_bus_handle_cmd(AspeedI2CBus *bus, uint64_t value) { uint8_t pool_start = 0; uint32_t reg_intr_sts = aspeed_i2c_bus_intr_sts_offset(bus); uint32_t reg_cmd = aspeed_i2c_bus_cmd_offset(bus); uint32_t reg_pool_ctrl = aspeed_i2c_bus_pool_ctrl_offset(bus); uint32_t reg_dma_len = aspeed_i2c_bus_dma_len_offset(bus); if (!aspeed_i2c_check_sram(bus)) { return; } if (trace_event_get_state_backends(TRACE_ASPEED_I2C_BUS_CMD)) { aspeed_i2c_bus_cmd_dump(bus); } if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_START_CMD)) { uint8_t state = aspeed_i2c_get_state(bus) & I2CD_MACTIVE ? I2CD_MSTARTR : I2CD_MSTART; uint8_t addr; aspeed_i2c_set_state(bus, state); addr = aspeed_i2c_get_addr(bus); if (i2c_start_transfer(bus->bus, extract32(addr, 1, 7), extract32(addr, 0, 1))) { SHARED_ARRAY_FIELD_DP32(bus->regs, reg_intr_sts, TX_NAK, 1); if (aspeed_i2c_bus_pkt_mode_en(bus)) { ARRAY_FIELD_DP32(bus->regs, I2CM_INTR_STS, PKT_CMD_FAIL, 1); } } else { /* START doesn't set TX_ACK in packet mode */ if (!aspeed_i2c_bus_pkt_mode_en(bus)) { SHARED_ARRAY_FIELD_DP32(bus->regs, reg_intr_sts, TX_ACK, 1); } } SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, M_START_CMD, 0); /* * The START command is also a TX command, as the slave * address is sent on the bus. Drop the TX flag if nothing * else needs to be sent in this sequence. */ if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, TX_BUFF_EN)) { if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_pool_ctrl, TX_COUNT) == 1) { SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, M_TX_CMD, 0); } else { /* * Increase the start index in the TX pool buffer to * skip the address byte. */ pool_start++; } } else if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, TX_DMA_EN)) { if (bus->regs[reg_dma_len] == 0) { SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, M_TX_CMD, 0); } } else { SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, M_TX_CMD, 0); } /* No slave found */ if (!i2c_bus_busy(bus->bus)) { if (aspeed_i2c_bus_pkt_mode_en(bus)) { ARRAY_FIELD_DP32(bus->regs, I2CM_INTR_STS, PKT_CMD_FAIL, 1); ARRAY_FIELD_DP32(bus->regs, I2CM_INTR_STS, PKT_CMD_DONE, 1); } return; } aspeed_i2c_set_state(bus, I2CD_MACTIVE); } if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_TX_CMD)) { aspeed_i2c_set_state(bus, I2CD_MTXD); if (aspeed_i2c_bus_send(bus, pool_start)) { SHARED_ARRAY_FIELD_DP32(bus->regs, reg_intr_sts, TX_NAK, 1); i2c_end_transfer(bus->bus); } else { SHARED_ARRAY_FIELD_DP32(bus->regs, reg_intr_sts, TX_ACK, 1); } SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, M_TX_CMD, 0); aspeed_i2c_set_state(bus, I2CD_MACTIVE); } if ((SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_RX_CMD) || SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_S_RX_CMD_LAST)) && !SHARED_ARRAY_FIELD_EX32(bus->regs, reg_intr_sts, RX_DONE)) { aspeed_i2c_handle_rx_cmd(bus); } if (SHARED_ARRAY_FIELD_EX32(bus->regs, reg_cmd, M_STOP_CMD)) { if (!(aspeed_i2c_get_state(bus) & I2CD_MACTIVE)) { qemu_log_mask(LOG_GUEST_ERROR, "%s: abnormal stop\n", __func__); SHARED_ARRAY_FIELD_DP32(bus->regs, reg_intr_sts, ABNORMAL, 1); if (aspeed_i2c_bus_pkt_mode_en(bus)) { ARRAY_FIELD_DP32(bus->regs, I2CM_INTR_STS, PKT_CMD_FAIL, 1); } } else { aspeed_i2c_set_state(bus, I2CD_MSTOP); i2c_end_transfer(bus->bus); SHARED_ARRAY_FIELD_DP32(bus->regs, reg_intr_sts, NORMAL_STOP, 1); } SHARED_ARRAY_FIELD_DP32(bus->regs, reg_cmd, M_STOP_CMD, 0); aspeed_i2c_set_state(bus, I2CD_IDLE); } if (aspeed_i2c_bus_pkt_mode_en(bus)) { ARRAY_FIELD_DP32(bus->regs, I2CM_INTR_STS, PKT_CMD_DONE, 1); } } static void aspeed_i2c_bus_new_write(AspeedI2CBus *bus, hwaddr offset, uint64_t value, unsigned size) { AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller); bool handle_rx; bool w1t; trace_aspeed_i2c_bus_write(bus->id, offset, size, value); switch (offset) { case A_I2CC_FUN_CTRL: if (SHARED_FIELD_EX32(value, SLAVE_EN)) { qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n", __func__); break; } bus->regs[R_I2CD_FUN_CTRL] = value & 0x007dc3ff; break; case A_I2CC_AC_TIMING: bus->regs[R_I2CC_AC_TIMING] = value & 0x1ffff0ff; break; case A_I2CC_MS_TXRX_BYTE_BUF: SHARED_ARRAY_FIELD_DP32(bus->regs, R_I2CC_MS_TXRX_BYTE_BUF, TX_BUF, value); break; case A_I2CC_POOL_CTRL: bus->regs[R_I2CC_POOL_CTRL] &= ~0xffffff; bus->regs[R_I2CC_POOL_CTRL] |= (value & 0xffffff); break; case A_I2CM_INTR_CTRL: bus->regs[R_I2CM_INTR_CTRL] = value & 0x0007f07f; break; case A_I2CM_INTR_STS: handle_rx = SHARED_ARRAY_FIELD_EX32(bus->regs, R_I2CM_INTR_STS, RX_DONE) && SHARED_FIELD_EX32(value, RX_DONE); /* In packet mode, clearing PKT_CMD_DONE clears other interrupts. */ if (aspeed_i2c_bus_pkt_mode_en(bus) && FIELD_EX32(value, I2CM_INTR_STS, PKT_CMD_DONE)) { bus->regs[R_I2CM_INTR_STS] &= 0xf0001000; if (!bus->regs[R_I2CM_INTR_STS]) { bus->controller->intr_status &= ~(1 << bus->id); qemu_irq_lower(aic->bus_get_irq(bus)); } break; } bus->regs[R_I2CM_INTR_STS] &= ~(value & 0xf007f07f); if (!bus->regs[R_I2CM_INTR_STS]) { bus->controller->intr_status &= ~(1 << bus->id); qemu_irq_lower(aic->bus_get_irq(bus)); } if (handle_rx && (SHARED_ARRAY_FIELD_EX32(bus->regs, R_I2CM_CMD, M_RX_CMD) || SHARED_ARRAY_FIELD_EX32(bus->regs, R_I2CM_CMD, M_S_RX_CMD_LAST))) { aspeed_i2c_handle_rx_cmd(bus); aspeed_i2c_bus_raise_interrupt(bus); } break; case A_I2CM_CMD: if (!aspeed_i2c_bus_is_enabled(bus)) { break; } if (!aspeed_i2c_bus_is_master(bus)) { qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n", __func__); break; } if (!aic->has_dma && (SHARED_FIELD_EX32(value, RX_DMA_EN) || SHARED_FIELD_EX32(value, TX_DMA_EN))) { qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n", __func__); break; } if (bus->regs[R_I2CM_INTR_STS] & 0xffff0000) { qemu_log_mask(LOG_UNIMP, "%s: Packet mode is not implemented\n", __func__); break; } value &= 0xff0ffbfb; if (ARRAY_FIELD_EX32(bus->regs, I2CM_CMD, W1_CTRL)) { bus->regs[R_I2CM_CMD] |= value; } else { bus->regs[R_I2CM_CMD] = value; } aspeed_i2c_bus_handle_cmd(bus, value); aspeed_i2c_bus_raise_interrupt(bus); break; case A_I2CM_DMA_TX_ADDR: bus->regs[R_I2CM_DMA_TX_ADDR] = FIELD_EX32(value, I2CM_DMA_TX_ADDR, ADDR); bus->regs[R_I2CC_DMA_ADDR] = FIELD_EX32(value, I2CM_DMA_TX_ADDR, ADDR); bus->regs[R_I2CC_DMA_LEN] = ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN, TX_BUF_LEN) + 1; break; case A_I2CM_DMA_RX_ADDR: bus->regs[R_I2CM_DMA_RX_ADDR] = FIELD_EX32(value, I2CM_DMA_RX_ADDR, ADDR); bus->regs[R_I2CC_DMA_ADDR] = FIELD_EX32(value, I2CM_DMA_RX_ADDR, ADDR); bus->regs[R_I2CC_DMA_LEN] = ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN, RX_BUF_LEN) + 1; break; case A_I2CM_DMA_LEN: w1t = ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN, RX_BUF_LEN_W1T) || ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN, TX_BUF_LEN_W1T); /* If none of the w1t bits are set, just write to the reg as normal. */ if (!w1t) { bus->regs[R_I2CM_DMA_LEN] = value; break; } if (ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN, RX_BUF_LEN_W1T)) { ARRAY_FIELD_DP32(bus->regs, I2CM_DMA_LEN, RX_BUF_LEN, FIELD_EX32(value, I2CM_DMA_LEN, RX_BUF_LEN)); } if (ARRAY_FIELD_EX32(bus->regs, I2CM_DMA_LEN, TX_BUF_LEN_W1T)) { ARRAY_FIELD_DP32(bus->regs, I2CM_DMA_LEN, TX_BUF_LEN, FIELD_EX32(value, I2CM_DMA_LEN, TX_BUF_LEN)); } break; case A_I2CM_DMA_LEN_STS: /* Writes clear to 0 */ bus->regs[R_I2CM_DMA_LEN_STS] = 0; break; case A_I2CC_DMA_ADDR: case A_I2CC_DMA_LEN: /* RO */ break; case A_I2CS_DMA_LEN_STS: case A_I2CS_DMA_TX_ADDR: case A_I2CS_DMA_RX_ADDR: case A_I2CS_DEV_ADDR: case A_I2CS_INTR_CTRL: case A_I2CS_INTR_STS: case A_I2CS_CMD: case A_I2CS_DMA_LEN: qemu_log_mask(LOG_UNIMP, "%s: Slave mode is not implemented\n", __func__); break; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, offset); } } static void aspeed_i2c_bus_old_write(AspeedI2CBus *bus, hwaddr offset, uint64_t value, unsigned size) { AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller); bool handle_rx; trace_aspeed_i2c_bus_write(bus->id, offset, size, value); switch (offset) { case A_I2CD_FUN_CTRL: if (SHARED_FIELD_EX32(value, SLAVE_EN)) { qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n", __func__); break; } bus->regs[R_I2CD_FUN_CTRL] = value & 0x0071C3FF; break; case A_I2CD_AC_TIMING1: bus->regs[R_I2CD_AC_TIMING1] = value & 0xFFFFF0F; break; case A_I2CD_AC_TIMING2: bus->regs[R_I2CD_AC_TIMING2] = value & 0x7; break; case A_I2CD_INTR_CTRL: bus->regs[R_I2CD_INTR_CTRL] = value & 0x7FFF; break; case A_I2CD_INTR_STS: handle_rx = SHARED_ARRAY_FIELD_EX32(bus->regs, R_I2CD_INTR_STS, RX_DONE) && SHARED_FIELD_EX32(value, RX_DONE); bus->regs[R_I2CD_INTR_STS] &= ~(value & 0x7FFF); if (!bus->regs[R_I2CD_INTR_STS]) { bus->controller->intr_status &= ~(1 << bus->id); qemu_irq_lower(aic->bus_get_irq(bus)); } if (handle_rx && (SHARED_ARRAY_FIELD_EX32(bus->regs, R_I2CD_CMD, M_RX_CMD) || SHARED_ARRAY_FIELD_EX32(bus->regs, R_I2CD_CMD, M_S_RX_CMD_LAST))) { aspeed_i2c_handle_rx_cmd(bus); aspeed_i2c_bus_raise_interrupt(bus); } break; case A_I2CD_DEV_ADDR: bus->regs[R_I2CD_DEV_ADDR] = value; break; case A_I2CD_POOL_CTRL: bus->regs[R_I2CD_POOL_CTRL] &= ~0xffffff; bus->regs[R_I2CD_POOL_CTRL] |= (value & 0xffffff); break; case A_I2CD_BYTE_BUF: SHARED_ARRAY_FIELD_DP32(bus->regs, R_I2CD_BYTE_BUF, TX_BUF, value); break; case A_I2CD_CMD: if (!aspeed_i2c_bus_is_enabled(bus)) { break; } if (!aspeed_i2c_bus_is_master(bus)) { qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n", __func__); break; } if (!aic->has_dma && (SHARED_FIELD_EX32(value, RX_DMA_EN) || SHARED_FIELD_EX32(value, TX_DMA_EN))) { qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n", __func__); break; } bus->regs[R_I2CD_CMD] &= ~0xFFFF; bus->regs[R_I2CD_CMD] |= value & 0xFFFF; aspeed_i2c_bus_handle_cmd(bus, value); aspeed_i2c_bus_raise_interrupt(bus); break; case A_I2CD_DMA_ADDR: if (!aic->has_dma) { qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n", __func__); break; } bus->regs[R_I2CD_DMA_ADDR] = value & 0x3ffffffc; break; case A_I2CD_DMA_LEN: if (!aic->has_dma) { qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n", __func__); break; } bus->regs[R_I2CD_DMA_LEN] = value & 0xfff; if (!bus->regs[R_I2CD_DMA_LEN]) { qemu_log_mask(LOG_UNIMP, "%s: invalid DMA length\n", __func__); } break; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, offset); } } static void aspeed_i2c_bus_write(void *opaque, hwaddr offset, uint64_t value, unsigned size) { AspeedI2CBus *bus = opaque; if (aspeed_i2c_is_new_mode(bus->controller)) { aspeed_i2c_bus_new_write(bus, offset, value, size); } else { aspeed_i2c_bus_old_write(bus, offset, value, size); } } static uint64_t aspeed_i2c_ctrl_read(void *opaque, hwaddr offset, unsigned size) { AspeedI2CState *s = opaque; switch (offset) { case A_I2C_CTRL_STATUS: return s->intr_status; case A_I2C_CTRL_GLOBAL: return s->ctrl_global; case A_I2C_CTRL_NEW_CLK_DIVIDER: if (aspeed_i2c_is_new_mode(s)) { return s->new_clk_divider; } qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, offset); break; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, offset); break; } return -1; } static void aspeed_i2c_ctrl_write(void *opaque, hwaddr offset, uint64_t value, unsigned size) { AspeedI2CState *s = opaque; switch (offset) { case A_I2C_CTRL_GLOBAL: s->ctrl_global = value; break; case A_I2C_CTRL_NEW_CLK_DIVIDER: if (aspeed_i2c_is_new_mode(s)) { s->new_clk_divider = value; } else { qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, offset); } break; case A_I2C_CTRL_STATUS: default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, offset); break; } } static const MemoryRegionOps aspeed_i2c_bus_ops = { .read = aspeed_i2c_bus_read, .write = aspeed_i2c_bus_write, .endianness = DEVICE_LITTLE_ENDIAN, }; static const MemoryRegionOps aspeed_i2c_ctrl_ops = { .read = aspeed_i2c_ctrl_read, .write = aspeed_i2c_ctrl_write, .endianness = DEVICE_LITTLE_ENDIAN, }; static uint64_t aspeed_i2c_pool_read(void *opaque, hwaddr offset, unsigned size) { AspeedI2CState *s = opaque; uint64_t ret = 0; int i; for (i = 0; i < size; i++) { ret |= (uint64_t) s->pool[offset + i] << (8 * i); } return ret; } static void aspeed_i2c_pool_write(void *opaque, hwaddr offset, uint64_t value, unsigned size) { AspeedI2CState *s = opaque; int i; for (i = 0; i < size; i++) { s->pool[offset + i] = (value >> (8 * i)) & 0xFF; } } static const MemoryRegionOps aspeed_i2c_pool_ops = { .read = aspeed_i2c_pool_read, .write = aspeed_i2c_pool_write, .endianness = DEVICE_LITTLE_ENDIAN, .valid = { .min_access_size = 1, .max_access_size = 4, }, }; static const VMStateDescription aspeed_i2c_bus_vmstate = { .name = TYPE_ASPEED_I2C, .version_id = 5, .minimum_version_id = 5, .fields = (VMStateField[]) { VMSTATE_UINT32_ARRAY(regs, AspeedI2CBus, ASPEED_I2C_NEW_NUM_REG), VMSTATE_END_OF_LIST() } }; static const VMStateDescription aspeed_i2c_vmstate = { .name = TYPE_ASPEED_I2C, .version_id = 2, .minimum_version_id = 2, .fields = (VMStateField[]) { VMSTATE_UINT32(intr_status, AspeedI2CState), VMSTATE_STRUCT_ARRAY(busses, AspeedI2CState, ASPEED_I2C_NR_BUSSES, 1, aspeed_i2c_bus_vmstate, AspeedI2CBus), VMSTATE_UINT8_ARRAY(pool, AspeedI2CState, ASPEED_I2C_MAX_POOL_SIZE), VMSTATE_END_OF_LIST() } }; static void aspeed_i2c_reset(DeviceState *dev) { AspeedI2CState *s = ASPEED_I2C(dev); s->intr_status = 0; } static void aspeed_i2c_instance_init(Object *obj) { AspeedI2CState *s = ASPEED_I2C(obj); AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s); int i; for (i = 0; i < aic->num_busses; i++) { object_initialize_child(obj, "bus[*]", &s->busses[i], TYPE_ASPEED_I2C_BUS); } } /* * Address Definitions (AST2400 and AST2500) * * 0x000 ... 0x03F: Global Register * 0x040 ... 0x07F: Device 1 * 0x080 ... 0x0BF: Device 2 * 0x0C0 ... 0x0FF: Device 3 * 0x100 ... 0x13F: Device 4 * 0x140 ... 0x17F: Device 5 * 0x180 ... 0x1BF: Device 6 * 0x1C0 ... 0x1FF: Device 7 * 0x200 ... 0x2FF: Buffer Pool (unused in linux driver) * 0x300 ... 0x33F: Device 8 * 0x340 ... 0x37F: Device 9 * 0x380 ... 0x3BF: Device 10 * 0x3C0 ... 0x3FF: Device 11 * 0x400 ... 0x43F: Device 12 * 0x440 ... 0x47F: Device 13 * 0x480 ... 0x4BF: Device 14 * 0x800 ... 0xFFF: Buffer Pool (unused in linux driver) */ static void aspeed_i2c_realize(DeviceState *dev, Error **errp) { int i; SysBusDevice *sbd = SYS_BUS_DEVICE(dev); AspeedI2CState *s = ASPEED_I2C(dev); AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s); sysbus_init_irq(sbd, &s->irq); memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_i2c_ctrl_ops, s, "aspeed.i2c", 0x1000); sysbus_init_mmio(sbd, &s->iomem); for (i = 0; i < aic->num_busses; i++) { Object *bus = OBJECT(&s->busses[i]); int offset = i < aic->gap ? 1 : 5; if (!object_property_set_link(bus, "controller", OBJECT(s), errp)) { return; } if (!object_property_set_uint(bus, "bus-id", i, errp)) { return; } if (!sysbus_realize(SYS_BUS_DEVICE(bus), errp)) { return; } memory_region_add_subregion(&s->iomem, aic->reg_size * (i + offset), &s->busses[i].mr); } memory_region_init_io(&s->pool_iomem, OBJECT(s), &aspeed_i2c_pool_ops, s, "aspeed.i2c-pool", aic->pool_size); memory_region_add_subregion(&s->iomem, aic->pool_base, &s->pool_iomem); if (aic->has_dma) { if (!s->dram_mr) { error_setg(errp, TYPE_ASPEED_I2C ": 'dram' link not set"); return; } address_space_init(&s->dram_as, s->dram_mr, TYPE_ASPEED_I2C "-dma-dram"); } } static Property aspeed_i2c_properties[] = { DEFINE_PROP_LINK("dram", AspeedI2CState, dram_mr, TYPE_MEMORY_REGION, MemoryRegion *), DEFINE_PROP_END_OF_LIST(), }; static void aspeed_i2c_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); dc->vmsd = &aspeed_i2c_vmstate; dc->reset = aspeed_i2c_reset; device_class_set_props(dc, aspeed_i2c_properties); dc->realize = aspeed_i2c_realize; dc->desc = "Aspeed I2C Controller"; } static const TypeInfo aspeed_i2c_info = { .name = TYPE_ASPEED_I2C, .parent = TYPE_SYS_BUS_DEVICE, .instance_init = aspeed_i2c_instance_init, .instance_size = sizeof(AspeedI2CState), .class_init = aspeed_i2c_class_init, .class_size = sizeof(AspeedI2CClass), .abstract = true, }; static void aspeed_i2c_bus_reset(DeviceState *dev) { AspeedI2CBus *s = ASPEED_I2C_BUS(dev); memset(s->regs, 0, sizeof(s->regs)); i2c_end_transfer(s->bus); } static void aspeed_i2c_bus_realize(DeviceState *dev, Error **errp) { AspeedI2CBus *s = ASPEED_I2C_BUS(dev); AspeedI2CClass *aic; g_autofree char *name = g_strdup_printf(TYPE_ASPEED_I2C_BUS ".%d", s->id); if (!s->controller) { error_setg(errp, TYPE_ASPEED_I2C_BUS ": 'controller' link not set"); return; } aic = ASPEED_I2C_GET_CLASS(s->controller); sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq); s->bus = i2c_init_bus(dev, name); memory_region_init_io(&s->mr, OBJECT(s), &aspeed_i2c_bus_ops, s, name, aic->reg_size); sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mr); } static Property aspeed_i2c_bus_properties[] = { DEFINE_PROP_UINT8("bus-id", AspeedI2CBus, id, 0), DEFINE_PROP_LINK("controller", AspeedI2CBus, controller, TYPE_ASPEED_I2C, AspeedI2CState *), DEFINE_PROP_END_OF_LIST(), }; static void aspeed_i2c_bus_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); dc->desc = "Aspeed I2C Bus"; dc->realize = aspeed_i2c_bus_realize; dc->reset = aspeed_i2c_bus_reset; device_class_set_props(dc, aspeed_i2c_bus_properties); } static const TypeInfo aspeed_i2c_bus_info = { .name = TYPE_ASPEED_I2C_BUS, .parent = TYPE_SYS_BUS_DEVICE, .instance_size = sizeof(AspeedI2CBus), .class_init = aspeed_i2c_bus_class_init, }; static qemu_irq aspeed_2400_i2c_bus_get_irq(AspeedI2CBus *bus) { return bus->controller->irq; } static uint8_t *aspeed_2400_i2c_bus_pool_base(AspeedI2CBus *bus) { uint8_t *pool_page = &bus->controller->pool[ARRAY_FIELD_EX32(bus->regs, I2CD_FUN_CTRL, POOL_PAGE_SEL) * 0x100]; return &pool_page[ARRAY_FIELD_EX32(bus->regs, I2CD_POOL_CTRL, OFFSET)]; } static void aspeed_2400_i2c_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); AspeedI2CClass *aic = ASPEED_I2C_CLASS(klass); dc->desc = "ASPEED 2400 I2C Controller"; aic->num_busses = 14; aic->reg_size = 0x40; aic->gap = 7; aic->bus_get_irq = aspeed_2400_i2c_bus_get_irq; aic->pool_size = 0x800; aic->pool_base = 0x800; aic->bus_pool_base = aspeed_2400_i2c_bus_pool_base; } static const TypeInfo aspeed_2400_i2c_info = { .name = TYPE_ASPEED_2400_I2C, .parent = TYPE_ASPEED_I2C, .class_init = aspeed_2400_i2c_class_init, }; static qemu_irq aspeed_2500_i2c_bus_get_irq(AspeedI2CBus *bus) { return bus->controller->irq; } static uint8_t *aspeed_2500_i2c_bus_pool_base(AspeedI2CBus *bus) { return &bus->controller->pool[bus->id * 0x10]; } static void aspeed_2500_i2c_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); AspeedI2CClass *aic = ASPEED_I2C_CLASS(klass); dc->desc = "ASPEED 2500 I2C Controller"; aic->num_busses = 14; aic->reg_size = 0x40; aic->gap = 7; aic->bus_get_irq = aspeed_2500_i2c_bus_get_irq; aic->pool_size = 0x100; aic->pool_base = 0x200; aic->bus_pool_base = aspeed_2500_i2c_bus_pool_base; aic->check_sram = true; aic->has_dma = true; } static const TypeInfo aspeed_2500_i2c_info = { .name = TYPE_ASPEED_2500_I2C, .parent = TYPE_ASPEED_I2C, .class_init = aspeed_2500_i2c_class_init, }; static qemu_irq aspeed_2600_i2c_bus_get_irq(AspeedI2CBus *bus) { return bus->irq; } static uint8_t *aspeed_2600_i2c_bus_pool_base(AspeedI2CBus *bus) { return &bus->controller->pool[bus->id * 0x20]; } static void aspeed_2600_i2c_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); AspeedI2CClass *aic = ASPEED_I2C_CLASS(klass); dc->desc = "ASPEED 2600 I2C Controller"; aic->num_busses = 16; aic->reg_size = 0x80; aic->gap = -1; /* no gap */ aic->bus_get_irq = aspeed_2600_i2c_bus_get_irq; aic->pool_size = 0x200; aic->pool_base = 0xC00; aic->bus_pool_base = aspeed_2600_i2c_bus_pool_base; aic->has_dma = true; } static const TypeInfo aspeed_2600_i2c_info = { .name = TYPE_ASPEED_2600_I2C, .parent = TYPE_ASPEED_I2C, .class_init = aspeed_2600_i2c_class_init, }; static void aspeed_1030_i2c_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); AspeedI2CClass *aic = ASPEED_I2C_CLASS(klass); dc->desc = "ASPEED 1030 I2C Controller"; aic->num_busses = 14; aic->reg_size = 0x80; aic->gap = -1; /* no gap */ aic->bus_get_irq = aspeed_2600_i2c_bus_get_irq; aic->pool_size = 0x200; aic->pool_base = 0xC00; aic->bus_pool_base = aspeed_2600_i2c_bus_pool_base; aic->has_dma = true; } static const TypeInfo aspeed_1030_i2c_info = { .name = TYPE_ASPEED_1030_I2C, .parent = TYPE_ASPEED_I2C, .class_init = aspeed_1030_i2c_class_init, }; static void aspeed_i2c_register_types(void) { type_register_static(&aspeed_i2c_bus_info); type_register_static(&aspeed_i2c_info); type_register_static(&aspeed_2400_i2c_info); type_register_static(&aspeed_2500_i2c_info); type_register_static(&aspeed_2600_i2c_info); type_register_static(&aspeed_1030_i2c_info); } type_init(aspeed_i2c_register_types) I2CBus *aspeed_i2c_get_bus(AspeedI2CState *s, int busnr) { AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s); I2CBus *bus = NULL; if (busnr >= 0 && busnr < aic->num_busses) { bus = s->busses[busnr].bus; } return bus; }