From 7709dbf12c0bb9a86c186c2c0f7ae67ce363dc80 Mon Sep 17 00:00:00 2001 From: BALATON Zoltan Date: Sat, 16 Dec 2017 23:42:14 +0100 Subject: [PATCH] ppc4xx_i2c: Implement basic I2C functions MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Enough to please U-Boot and make it able to detect SDRAM SPD EEPROMs Signed-off-by: François Revol Signed-off-by: BALATON Zoltan Reviewed-by: David Gibson Signed-off-by: David Gibson --- hw/i2c/ppc4xx_i2c.c | 198 +++++++++++++++++++++++++++++++++++++------- include/hw/i2c/ppc4xx_i2c.h | 3 + 2 files changed, 171 insertions(+), 30 deletions(-) diff --git a/hw/i2c/ppc4xx_i2c.c b/hw/i2c/ppc4xx_i2c.c index 5a6bde951e..e873a445da 100644 --- a/hw/i2c/ppc4xx_i2c.c +++ b/hw/i2c/ppc4xx_i2c.c @@ -2,6 +2,8 @@ * PPC4xx I2C controller emulation * * Copyright (c) 2007 Jocelyn Mayer + * Copyright (c) 2012 François Revol + * Copyright (c) 2016 BALATON Zoltan * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal @@ -25,26 +27,118 @@ #include "qemu/osdep.h" #include "qapi/error.h" #include "qemu-common.h" +#include "qemu/log.h" #include "cpu.h" #include "hw/hw.h" #include "hw/i2c/ppc4xx_i2c.h" -/*#define DEBUG_I2C*/ +#define PPC4xx_I2C_MEM_SIZE 0x12 -#define PPC4xx_I2C_MEM_SIZE 0x11 +#define IIC_CNTL_PT (1 << 0) +#define IIC_CNTL_READ (1 << 1) +#define IIC_CNTL_CHT (1 << 2) +#define IIC_CNTL_RPST (1 << 3) + +#define IIC_STS_PT (1 << 0) +#define IIC_STS_ERR (1 << 2) +#define IIC_STS_MDBS (1 << 5) + +#define IIC_EXTSTS_XFRA (1 << 0) + +#define IIC_XTCNTLSS_SRST (1 << 0) + +static void ppc4xx_i2c_reset(DeviceState *s) +{ + PPC4xxI2CState *i2c = PPC4xx_I2C(s); + + /* FIXME: Should also reset bus? + *if (s->address != ADDR_RESET) { + * i2c_end_transfer(s->bus); + *} + */ + + i2c->mdata = 0; + i2c->lmadr = 0; + i2c->hmadr = 0; + i2c->cntl = 0; + i2c->mdcntl = 0; + i2c->sts = 0; + i2c->extsts = 0x8f; + i2c->sdata = 0; + i2c->lsadr = 0; + i2c->hsadr = 0; + i2c->clkdiv = 0; + i2c->intrmsk = 0; + i2c->xfrcnt = 0; + i2c->xtcntlss = 0; + i2c->directcntl = 0x0f; + i2c->intr = 0; +} + +static inline bool ppc4xx_i2c_is_master(PPC4xxI2CState *i2c) +{ + return true; +} static uint64_t ppc4xx_i2c_readb(void *opaque, hwaddr addr, unsigned int size) { PPC4xxI2CState *i2c = PPC4xx_I2C(opaque); uint64_t ret; -#ifdef DEBUG_I2C - printf("%s: addr " TARGET_FMT_plx "\n", __func__, addr); -#endif switch (addr) { case 0x00: - /*i2c_readbyte(&i2c->mdata);*/ ret = i2c->mdata; + if (ppc4xx_i2c_is_master(i2c)) { + ret = 0xff; + + if (!(i2c->sts & IIC_STS_MDBS)) { + qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Trying to read " + "without starting transfer\n", + TYPE_PPC4xx_I2C, __func__); + } else { + int pending = (i2c->cntl >> 4) & 3; + + /* get the next byte */ + int byte = i2c_recv(i2c->bus); + + if (byte < 0) { + qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: read failed " + "for device 0x%02x\n", TYPE_PPC4xx_I2C, + __func__, i2c->lmadr); + ret = 0xff; + } else { + ret = byte; + /* Raise interrupt if enabled */ + /*ppc4xx_i2c_raise_interrupt(i2c)*/; + } + + if (!pending) { + i2c->sts &= ~IIC_STS_MDBS; + /*i2c_end_transfer(i2c->bus);*/ + /*} else if (i2c->cntl & (IIC_CNTL_RPST | IIC_CNTL_CHT)) {*/ + } else if (pending) { + /* current smbus implementation doesn't like + multibyte xfer repeated start */ + i2c_end_transfer(i2c->bus); + if (i2c_start_transfer(i2c->bus, i2c->lmadr >> 1, 1)) { + /* if non zero is returned, the adress is not valid */ + i2c->sts &= ~IIC_STS_PT; + i2c->sts |= IIC_STS_ERR; + i2c->extsts |= IIC_EXTSTS_XFRA; + } else { + /*i2c->sts |= IIC_STS_PT;*/ + i2c->sts |= IIC_STS_MDBS; + i2c->sts &= ~IIC_STS_ERR; + i2c->extsts = 0; + } + } + pending--; + i2c->cntl = (i2c->cntl & 0xcf) | (pending << 4); + } + } else { + qemu_log_mask(LOG_UNIMP, "[%s]%s: slave mode not implemented\n", + TYPE_PPC4xx_I2C, __func__); + } break; case 0x02: ret = i2c->sdata; @@ -88,13 +182,15 @@ static uint64_t ppc4xx_i2c_readb(void *opaque, hwaddr addr, unsigned int size) case 0x10: ret = i2c->directcntl; break; + case 0x11: + ret = i2c->intr; + break; default: - ret = 0x00; + qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad address at offset 0x%" + HWADDR_PRIx "\n", TYPE_PPC4xx_I2C, __func__, addr); + ret = 0; break; } -#ifdef DEBUG_I2C - printf("%s: addr " TARGET_FMT_plx " %02" PRIx64 "\n", __func__, addr, ret); -#endif return ret; } @@ -103,26 +199,70 @@ static void ppc4xx_i2c_writeb(void *opaque, hwaddr addr, uint64_t value, unsigned int size) { PPC4xxI2CState *i2c = opaque; -#ifdef DEBUG_I2C - printf("%s: addr " TARGET_FMT_plx " val %08" PRIx64 "\n", - __func__, addr, value); -#endif + switch (addr) { case 0x00: i2c->mdata = value; - /*i2c_sendbyte(&i2c->mdata);*/ + if (!i2c_bus_busy(i2c->bus)) { + /* assume we start a write transfer */ + if (i2c_start_transfer(i2c->bus, i2c->lmadr >> 1, 0)) { + /* if non zero is returned, the adress is not valid */ + i2c->sts &= ~IIC_STS_PT; + i2c->sts |= IIC_STS_ERR; + i2c->extsts |= IIC_EXTSTS_XFRA; + } else { + i2c->sts |= IIC_STS_PT; + i2c->sts &= ~IIC_STS_ERR; + i2c->extsts = 0; + } + } + if (i2c_bus_busy(i2c->bus)) { + if (i2c_send(i2c->bus, i2c->mdata)) { + /* if the target return non zero then end the transfer */ + i2c->sts &= ~IIC_STS_PT; + i2c->sts |= IIC_STS_ERR; + i2c->extsts |= IIC_EXTSTS_XFRA; + i2c_end_transfer(i2c->bus); + } + } break; case 0x02: i2c->sdata = value; break; case 0x04: i2c->lmadr = value; + if (i2c_bus_busy(i2c->bus)) { + i2c_end_transfer(i2c->bus); + } break; case 0x05: i2c->hmadr = value; break; case 0x06: i2c->cntl = value; + if (i2c->cntl & IIC_CNTL_PT) { + if (i2c->cntl & IIC_CNTL_READ) { + if (i2c_bus_busy(i2c->bus)) { + /* end previous transfer */ + i2c->sts &= ~IIC_STS_PT; + i2c_end_transfer(i2c->bus); + } + if (i2c_start_transfer(i2c->bus, i2c->lmadr >> 1, 1)) { + /* if non zero is returned, the adress is not valid */ + i2c->sts &= ~IIC_STS_PT; + i2c->sts |= IIC_STS_ERR; + i2c->extsts |= IIC_EXTSTS_XFRA; + } else { + /*i2c->sts |= IIC_STS_PT;*/ + i2c->sts |= IIC_STS_MDBS; + i2c->sts &= ~IIC_STS_ERR; + i2c->extsts = 0; + } + } else { + /* we actually already did the write transfer... */ + i2c->sts &= ~IIC_STS_PT; + } + } break; case 0x07: i2c->mdcntl = value & 0xDF; @@ -135,6 +275,7 @@ static void ppc4xx_i2c_writeb(void *opaque, hwaddr addr, uint64_t value, break; case 0x0A: i2c->lsadr = value; + /*i2c_set_slave_address(i2c->bus, i2c->lsadr);*/ break; case 0x0B: i2c->hsadr = value; @@ -149,11 +290,23 @@ static void ppc4xx_i2c_writeb(void *opaque, hwaddr addr, uint64_t value, i2c->xfrcnt = value & 0x77; break; case 0x0F: + if (value & IIC_XTCNTLSS_SRST) { + /* Is it actually a full reset? U-Boot sets some regs before */ + ppc4xx_i2c_reset(DEVICE(i2c)); + break; + } i2c->xtcntlss = value; break; case 0x10: i2c->directcntl = value & 0x7; break; + case 0x11: + i2c->intr = value; + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad address at offset 0x%" + HWADDR_PRIx "\n", TYPE_PPC4xx_I2C, __func__, addr); + break; } } @@ -167,21 +320,6 @@ static const MemoryRegionOps ppc4xx_i2c_ops = { .endianness = DEVICE_NATIVE_ENDIAN, }; -static void ppc4xx_i2c_reset(DeviceState *s) -{ - PPC4xxI2CState *i2c = PPC4xx_I2C(s); - - i2c->mdata = 0x00; - i2c->sdata = 0x00; - i2c->cntl = 0x00; - i2c->mdcntl = 0x00; - i2c->sts = 0x00; - i2c->extsts = 0x00; - i2c->clkdiv = 0x00; - i2c->xfrcnt = 0x00; - i2c->directcntl = 0x0F; -} - static void ppc4xx_i2c_init(Object *o) { PPC4xxI2CState *s = PPC4xx_I2C(o); diff --git a/include/hw/i2c/ppc4xx_i2c.h b/include/hw/i2c/ppc4xx_i2c.h index 3450bda577..3c603071bd 100644 --- a/include/hw/i2c/ppc4xx_i2c.h +++ b/include/hw/i2c/ppc4xx_i2c.h @@ -2,6 +2,8 @@ * PPC4xx I2C controller emulation * * Copyright (c) 2007 Jocelyn Mayer + * Copyright (c) 2012 François Revol + * Copyright (c) 2016 BALATON Zoltan * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal @@ -55,6 +57,7 @@ typedef struct PPC4xxI2CState { uint8_t xfrcnt; uint8_t xtcntlss; uint8_t directcntl; + uint8_t intr; } PPC4xxI2CState; #endif /* PPC4XX_I2C_H */ -- 2.11.4.GIT