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	 afb6e20429
			
		
	
	
		afb6e20429
		
	
	
	
	
		
			
			Rewrite to make it closer to how real device works so that guest OS drivers can access I2C devices. Previously this was only a hack to allow U-Boot to get past accessing SPD EEPROMs but to support other I2C devices and allow guests to access them we need to model real device more properly. Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu> Reviewed-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
		
			
				
	
	
		
			375 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			375 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * PPC4xx I2C controller emulation
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|  *
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|  * Copyright (c) 2007 Jocelyn Mayer
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|  * Copyright (c) 2012 François Revol
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|  * Copyright (c) 2016-2018 BALATON Zoltan
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|  *
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|  * Permission is hereby granted, free of charge, to any person obtaining a copy
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|  * of this software and associated documentation files (the "Software"), to deal
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|  * in the Software without restriction, including without limitation the rights
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|  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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|  * copies of the Software, and to permit persons to whom the Software is
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|  * furnished to do so, subject to the following conditions:
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|  *
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|  * The above copyright notice and this permission notice shall be included in
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|  * all copies or substantial portions of the Software.
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|  *
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|  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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|  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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|  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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|  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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|  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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|  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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|  * THE SOFTWARE.
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|  */
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| 
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| #include "qemu/osdep.h"
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| #include "qemu-common.h"
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| #include "qemu/log.h"
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| #include "cpu.h"
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| #include "hw/hw.h"
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| #include "hw/i2c/ppc4xx_i2c.h"
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| #include "bitbang_i2c.h"
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| 
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| #define PPC4xx_I2C_MEM_SIZE 18
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| 
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| enum {
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|     IIC_MDBUF = 0,
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|     /* IIC_SDBUF = 2, */
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|     IIC_LMADR = 4,
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|     IIC_HMADR,
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|     IIC_CNTL,
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|     IIC_MDCNTL,
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|     IIC_STS,
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|     IIC_EXTSTS,
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|     IIC_LSADR,
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|     IIC_HSADR,
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|     IIC_CLKDIV,
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|     IIC_INTRMSK,
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|     IIC_XFRCNT,
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|     IIC_XTCNTLSS,
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|     IIC_DIRECTCNTL
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|     /* IIC_INTR */
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| };
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| 
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| #define IIC_CNTL_PT         (1 << 0)
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| #define IIC_CNTL_READ       (1 << 1)
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| #define IIC_CNTL_CHT        (1 << 2)
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| #define IIC_CNTL_RPST       (1 << 3)
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| #define IIC_CNTL_AMD        (1 << 6)
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| #define IIC_CNTL_HMT        (1 << 7)
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| 
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| #define IIC_MDCNTL_EINT     (1 << 2)
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| #define IIC_MDCNTL_ESM      (1 << 3)
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| #define IIC_MDCNTL_FMDB     (1 << 6)
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| 
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| #define IIC_STS_PT          (1 << 0)
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| #define IIC_STS_IRQA        (1 << 1)
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| #define IIC_STS_ERR         (1 << 2)
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| #define IIC_STS_MDBF        (1 << 4)
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| #define IIC_STS_MDBS        (1 << 5)
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| 
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| #define IIC_EXTSTS_XFRA     (1 << 0)
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| #define IIC_EXTSTS_BCS_FREE (4 << 4)
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| #define IIC_EXTSTS_BCS_BUSY (5 << 4)
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| 
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| #define IIC_INTRMSK_EIMTC   (1 << 0)
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| #define IIC_INTRMSK_EITA    (1 << 1)
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| #define IIC_INTRMSK_EIIC    (1 << 2)
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| #define IIC_INTRMSK_EIHE    (1 << 3)
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| 
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| #define IIC_XTCNTLSS_SRST   (1 << 0)
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| 
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| #define IIC_DIRECTCNTL_SDAC (1 << 3)
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| #define IIC_DIRECTCNTL_SCLC (1 << 2)
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| #define IIC_DIRECTCNTL_MSDA (1 << 1)
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| #define IIC_DIRECTCNTL_MSCL (1 << 0)
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| 
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| static void ppc4xx_i2c_reset(DeviceState *s)
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| {
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|     PPC4xxI2CState *i2c = PPC4xx_I2C(s);
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| 
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|     i2c->mdidx = -1;
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|     memset(i2c->mdata, 0, ARRAY_SIZE(i2c->mdata));
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|     /* [hl][ms]addr are not affected by reset */
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|     i2c->cntl = 0;
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|     i2c->mdcntl = 0;
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|     i2c->sts = 0;
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|     i2c->extsts = IIC_EXTSTS_BCS_FREE;
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|     i2c->clkdiv = 0;
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|     i2c->intrmsk = 0;
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|     i2c->xfrcnt = 0;
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|     i2c->xtcntlss = 0;
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|     i2c->directcntl = 0xf; /* all non-reserved bits set */
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| }
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| 
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| static uint64_t ppc4xx_i2c_readb(void *opaque, hwaddr addr, unsigned int size)
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| {
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|     PPC4xxI2CState *i2c = PPC4xx_I2C(opaque);
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|     uint64_t ret;
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|     int i;
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| 
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|     switch (addr) {
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|     case IIC_MDBUF:
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|         if (i2c->mdidx < 0) {
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|             ret = 0xff;
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|             break;
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|         }
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|         ret = i2c->mdata[0];
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|         if (i2c->mdidx == 3) {
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|             i2c->sts &= ~IIC_STS_MDBF;
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|         } else if (i2c->mdidx == 0) {
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|             i2c->sts &= ~IIC_STS_MDBS;
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|         }
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|         for (i = 0; i < i2c->mdidx; i++) {
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|             i2c->mdata[i] = i2c->mdata[i + 1];
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|         }
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|         if (i2c->mdidx >= 0) {
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|             i2c->mdidx--;
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|         }
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|         break;
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|     case IIC_LMADR:
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|         ret = i2c->lmadr;
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|         break;
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|     case IIC_HMADR:
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|         ret = i2c->hmadr;
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|         break;
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|     case IIC_CNTL:
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|         ret = i2c->cntl;
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|         break;
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|     case IIC_MDCNTL:
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|         ret = i2c->mdcntl;
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|         break;
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|     case IIC_STS:
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|         ret = i2c->sts;
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|         break;
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|     case IIC_EXTSTS:
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|         ret = i2c_bus_busy(i2c->bus) ?
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|               IIC_EXTSTS_BCS_BUSY : IIC_EXTSTS_BCS_FREE;
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|         break;
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|     case IIC_LSADR:
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|         ret = i2c->lsadr;
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|         break;
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|     case IIC_HSADR:
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|         ret = i2c->hsadr;
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|         break;
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|     case IIC_CLKDIV:
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|         ret = i2c->clkdiv;
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|         break;
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|     case IIC_INTRMSK:
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|         ret = i2c->intrmsk;
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|         break;
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|     case IIC_XFRCNT:
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|         ret = i2c->xfrcnt;
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|         break;
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|     case IIC_XTCNTLSS:
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|         ret = i2c->xtcntlss;
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|         break;
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|     case IIC_DIRECTCNTL:
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|         ret = i2c->directcntl;
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|         break;
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|     default:
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|         if (addr < PPC4xx_I2C_MEM_SIZE) {
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|             qemu_log_mask(LOG_UNIMP, "%s: Unimplemented register 0x%"
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|                           HWADDR_PRIx "\n", __func__, addr);
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|         } else {
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|             qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad address 0x%"
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|                           HWADDR_PRIx "\n", __func__, addr);
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|         }
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|         ret = 0;
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|         break;
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|     }
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|     return ret;
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| }
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| 
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| static void ppc4xx_i2c_writeb(void *opaque, hwaddr addr, uint64_t value,
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|                               unsigned int size)
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| {
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|     PPC4xxI2CState *i2c = opaque;
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| 
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|     switch (addr) {
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|     case IIC_MDBUF:
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|         if (i2c->mdidx >= 3) {
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|             break;
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|         }
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|         i2c->mdata[++i2c->mdidx] = value;
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|         if (i2c->mdidx == 3) {
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|             i2c->sts |= IIC_STS_MDBF;
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|         } else if (i2c->mdidx == 0) {
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|             i2c->sts |= IIC_STS_MDBS;
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|         }
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|         break;
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|     case IIC_LMADR:
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|         i2c->lmadr = value;
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|         break;
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|     case IIC_HMADR:
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|         i2c->hmadr = value;
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|         break;
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|     case IIC_CNTL:
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|         i2c->cntl = value & ~IIC_CNTL_PT;
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|         if (value & IIC_CNTL_AMD) {
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|             qemu_log_mask(LOG_UNIMP, "%s: only 7 bit addresses supported\n",
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|                           __func__);
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|         }
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|         if (value & IIC_CNTL_HMT && i2c_bus_busy(i2c->bus)) {
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|             i2c_end_transfer(i2c->bus);
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|             if (i2c->mdcntl & IIC_MDCNTL_EINT &&
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|                 i2c->intrmsk & IIC_INTRMSK_EIHE) {
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|                 i2c->sts |= IIC_STS_IRQA;
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|                 qemu_irq_raise(i2c->irq);
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|             }
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|         } else if (value & IIC_CNTL_PT) {
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|             int recv = (value & IIC_CNTL_READ) >> 1;
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|             int tct = value >> 4 & 3;
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|             int i;
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| 
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|             if (recv && (i2c->lmadr >> 1) >= 0x50 && (i2c->lmadr >> 1) < 0x58) {
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|                 /* smbus emulation does not like multi byte reads w/o restart */
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|                 value |= IIC_CNTL_RPST;
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|             }
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| 
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|             for (i = 0; i <= tct; i++) {
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|                 if (!i2c_bus_busy(i2c->bus)) {
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|                     i2c->extsts = IIC_EXTSTS_BCS_FREE;
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|                     if (i2c_start_transfer(i2c->bus, i2c->lmadr >> 1, recv)) {
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|                         i2c->sts |= IIC_STS_ERR;
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|                         i2c->extsts |= IIC_EXTSTS_XFRA;
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|                         break;
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|                     } else {
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|                         i2c->sts &= ~IIC_STS_ERR;
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|                     }
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|                 }
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|                 if (!(i2c->sts & IIC_STS_ERR) &&
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|                     i2c_send_recv(i2c->bus, &i2c->mdata[i], !recv)) {
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|                     i2c->sts |= IIC_STS_ERR;
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|                     i2c->extsts |= IIC_EXTSTS_XFRA;
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|                     break;
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|                 }
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|                 if (value & IIC_CNTL_RPST || !(value & IIC_CNTL_CHT)) {
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|                     i2c_end_transfer(i2c->bus);
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|                 }
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|             }
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|             i2c->xfrcnt = i;
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|             i2c->mdidx = i - 1;
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|             if (recv && i2c->mdidx >= 0) {
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|                 i2c->sts |= IIC_STS_MDBS;
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|             }
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|             if (recv && i2c->mdidx == 3) {
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|                 i2c->sts |= IIC_STS_MDBF;
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|             }
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|             if (i && i2c->mdcntl & IIC_MDCNTL_EINT &&
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|                 i2c->intrmsk & IIC_INTRMSK_EIMTC) {
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|                 i2c->sts |= IIC_STS_IRQA;
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|                 qemu_irq_raise(i2c->irq);
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|             }
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|         }
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|         break;
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|     case IIC_MDCNTL:
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|         i2c->mdcntl = value & 0x3d;
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|         if (value & IIC_MDCNTL_ESM) {
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|             qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n",
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|                           __func__);
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|         }
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|         if (value & IIC_MDCNTL_FMDB) {
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|             i2c->mdidx = -1;
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|             memset(i2c->mdata, 0, ARRAY_SIZE(i2c->mdata));
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|             i2c->sts &= ~(IIC_STS_MDBF | IIC_STS_MDBS);
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|         }
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|         break;
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|     case IIC_STS:
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|         i2c->sts &= ~(value & 0x0a);
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|         if (value & IIC_STS_IRQA && i2c->mdcntl & IIC_MDCNTL_EINT) {
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|             qemu_irq_lower(i2c->irq);
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|         }
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|         break;
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|     case IIC_EXTSTS:
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|         i2c->extsts &= ~(value & 0x8f);
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|         break;
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|     case IIC_LSADR:
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|         i2c->lsadr = value;
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|         break;
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|     case IIC_HSADR:
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|         i2c->hsadr = value;
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|         break;
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|     case IIC_CLKDIV:
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|         i2c->clkdiv = value;
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|         break;
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|     case IIC_INTRMSK:
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|         i2c->intrmsk = value;
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|         break;
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|     case IIC_XFRCNT:
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|         i2c->xfrcnt = value & 0x77;
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|         break;
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|     case IIC_XTCNTLSS:
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|         i2c->xtcntlss &= ~(value & 0xf0);
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|         if (value & IIC_XTCNTLSS_SRST) {
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|             /* Is it actually a full reset? U-Boot sets some regs before */
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|             ppc4xx_i2c_reset(DEVICE(i2c));
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|             break;
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|         }
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|         break;
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|     case IIC_DIRECTCNTL:
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|         i2c->directcntl = value & (IIC_DIRECTCNTL_SDAC & IIC_DIRECTCNTL_SCLC);
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|         i2c->directcntl |= (value & IIC_DIRECTCNTL_SCLC ? 1 : 0);
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|         bitbang_i2c_set(i2c->bitbang, BITBANG_I2C_SCL,
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|                         i2c->directcntl & IIC_DIRECTCNTL_MSCL);
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|         i2c->directcntl |= bitbang_i2c_set(i2c->bitbang, BITBANG_I2C_SDA,
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|                                (value & IIC_DIRECTCNTL_SDAC) != 0) << 1;
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|         break;
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|     default:
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|         if (addr < PPC4xx_I2C_MEM_SIZE) {
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|             qemu_log_mask(LOG_UNIMP, "%s: Unimplemented register 0x%"
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|                           HWADDR_PRIx "\n", __func__, addr);
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|         } else {
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|             qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad address 0x%"
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|                           HWADDR_PRIx "\n", __func__, addr);
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|         }
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|         break;
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|     }
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| }
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| 
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| static const MemoryRegionOps ppc4xx_i2c_ops = {
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|     .read = ppc4xx_i2c_readb,
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|     .write = ppc4xx_i2c_writeb,
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|     .valid.min_access_size = 1,
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|     .valid.max_access_size = 4,
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|     .impl.min_access_size = 1,
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|     .impl.max_access_size = 1,
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|     .endianness = DEVICE_NATIVE_ENDIAN,
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| };
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| 
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| static void ppc4xx_i2c_init(Object *o)
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| {
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|     PPC4xxI2CState *s = PPC4xx_I2C(o);
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| 
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|     memory_region_init_io(&s->iomem, OBJECT(s), &ppc4xx_i2c_ops, s,
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|                           TYPE_PPC4xx_I2C, PPC4xx_I2C_MEM_SIZE);
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|     sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
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|     sysbus_init_irq(SYS_BUS_DEVICE(s), &s->irq);
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|     s->bus = i2c_init_bus(DEVICE(s), "i2c");
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|     s->bitbang = bitbang_i2c_init(s->bus);
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| }
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| 
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| static void ppc4xx_i2c_class_init(ObjectClass *klass, void *data)
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| {
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|     DeviceClass *dc = DEVICE_CLASS(klass);
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| 
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|     dc->reset = ppc4xx_i2c_reset;
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| }
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| 
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| static const TypeInfo ppc4xx_i2c_type_info = {
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|     .name = TYPE_PPC4xx_I2C,
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|     .parent = TYPE_SYS_BUS_DEVICE,
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|     .instance_size = sizeof(PPC4xxI2CState),
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|     .instance_init = ppc4xx_i2c_init,
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|     .class_init = ppc4xx_i2c_class_init,
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| };
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| 
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| static void ppc4xx_i2c_register_types(void)
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| {
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|     type_register_static(&ppc4xx_i2c_type_info);
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| }
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| 
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| type_init(ppc4xx_i2c_register_types)
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