fsl_i2c: add workaround for the erratum I2C A004447

This workaround is for the erratum I2C A004447. Device reference
manual provides a scheme that allows the I2C master controller
to generate nine SCL pulses, which enable an I2C slave device
that held SDA low to release SDA. However, due to this erratum,
this scheme no longer works. In addition, when I2C is used as
a source of the PBL, the state machine is not able to recover.

At the same time, delete the reduplicative definition of SVR_VER
and SVR_REV. The SVR_REV is the low 8 bits rather than the low 16
bits of svr. And we use the CONFIG_SYS_FSL_A004447_SVR_REV macro
instead of hard-code value 0x10, 0x11 and 0x20.

The CONFIG_SYS_FSL_A004447_SVR_REV = 0x00 represents that one
version of platform has this I2C errata. So enable this errata
by IS_SVR_REV(svr, maj, min) function.

Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com>
Signed-off-by: Chunhe Lan <Chunhe.Lan@freescale.com>
Cc: Scott Wood <scottwood@freescale.com>
Cc: Heiko Schocher <hs@denx.de>

arch/powerpc/cpu/mpc85xx/cmd_errata.c

@@ -248,6 +248,11 @@ static int do_errata(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 #ifdef CONFIG_SYS_FSL_ERRATUM_A005812
 	puts("Work-around for Erratum A-005812 enabled\n");
 #endif
+#ifdef CONFIG_SYS_FSL_ERRATUM_I2C_A004447
+	if ((SVR_SOC_VER(svr) == SVR_8548 && IS_SVR_REV(svr, 3, 1)) ||
+	    (SVR_REV(svr) <= CONFIG_SYS_FSL_A004447_SVR_REV))
+		puts("Work-around for Erratum I2C-A004447 enabled\n");
+#endif
 	return 0;
 }
 

arch/powerpc/include/asm/config_mpc85xx.h

@@ -67,6 +67,8 @@
 #define CONFIG_SYS_FSL_SRIO_IB_WIN_NUM	5
 #define CONFIG_SYS_FSL_RMU
 #define CONFIG_SYS_FSL_SRIO_MSG_UNIT_NUM	2
+#define CONFIG_SYS_FSL_ERRATUM_I2C_A004447
+#define CONFIG_SYS_FSL_A004447_SVR_REV	0x00
 
 #elif defined(CONFIG_MPC8555)
 #define CONFIG_MAX_CPUS			1
@@ -132,6 +134,8 @@
 #define CONFIG_SYS_FSL_ERRATUM_IFC_A002769
 #define CONFIG_SYS_FSL_ERRATUM_P1010_A003549
 #define CONFIG_SYS_FSL_ERRATUM_IFC_A003399
+#define CONFIG_SYS_FSL_ERRATUM_I2C_A004447
+#define CONFIG_SYS_FSL_A004447_SVR_REV	0x10
 
 /* P1011 is single core version of P1020 */
 #elif defined(CONFIG_P1011)
@@ -249,6 +253,8 @@
 #define CONFIG_SYS_FM_MURAM_SIZE	0x10000
 #define CONFIG_SYS_FSL_PCIE_COMPAT	"fsl,qoriq-pcie-v2.2"
 #define CONFIG_SYS_CCSRBAR_DEFAULT	0xff600000
+#define CONFIG_SYS_FSL_ERRATUM_I2C_A004447
+#define CONFIG_SYS_FSL_A004447_SVR_REV	0x11
 
 /* P1024 is lower end variant of P1020 */
 #elif defined(CONFIG_P1024)
@@ -334,6 +340,8 @@
 #define CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 0xf0000000
 #define CONFIG_SYS_FSL_ERRATUM_SRIO_A004034
 #define CONFIG_SYS_FSL_ERRATUM_A004849
+#define CONFIG_SYS_FSL_ERRATUM_I2C_A004447
+#define CONFIG_SYS_FSL_A004447_SVR_REV	0x11
 
 #elif defined(CONFIG_PPC_P3041)
 #define CONFIG_SYS_FSL_QORIQ_CHASSIS1
@@ -369,6 +377,8 @@
 #define CONFIG_SYS_FSL_ERRATUM_SRIO_A004034
 #define CONFIG_SYS_FSL_ERRATUM_A004849
 #define CONFIG_SYS_FSL_ERRATUM_A005812
+#define CONFIG_SYS_FSL_ERRATUM_I2C_A004447
+#define CONFIG_SYS_FSL_A004447_SVR_REV	0x20
 
 #elif defined(CONFIG_PPC_P4080) /* also supports P4040 */
 #define CONFIG_SYS_FSL_QORIQ_CHASSIS1
@@ -415,6 +425,8 @@
 #define CONFIG_SYS_FSL_ERRATUM_A004580
 #define CONFIG_SYS_P4080_ERRATUM_PCIE_A003
 #define CONFIG_SYS_FSL_ERRATUM_A005812
+#define CONFIG_SYS_FSL_ERRATUM_I2C_A004447
+#define CONFIG_SYS_FSL_A004447_SVR_REV	0x20
 
 #elif defined(CONFIG_PPC_P5020) /* also supports P5010 */
 #define CONFIG_SYS_PPC64		/* 64-bit core */
@@ -446,6 +458,8 @@
 #define CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV	0x10
 #define CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 0xc0000000
 #define CONFIG_SYS_FSL_ERRATUM_SRIO_A004034
+#define CONFIG_SYS_FSL_ERRATUM_I2C_A004447
+#define CONFIG_SYS_FSL_A004447_SVR_REV	0x20
 
 #elif defined(CONFIG_PPC_P5040)
 #define CONFIG_SYS_PPC64
@@ -510,6 +524,8 @@
 #define CONFIG_SYS_FSL_ERRATUM_ESDHC111
 #define CONFIG_SYS_FSL_ESDHC_P1010_BROKEN_SDCLK
 #define CONFIG_SYS_FSL_PCIE_COMPAT	"fsl,qoriq-pcie-v2.2"
+#define CONFIG_SYS_FSL_ERRATUM_I2C_A004447
+#define CONFIG_SYS_FSL_A004447_SVR_REV	0x11
 
 #elif defined(CONFIG_PPC_T4240) || defined(CONFIG_PPC_T4160)
 #define CONFIG_E6500

arch/powerpc/include/asm/fsl_i2c.h

@@ -54,6 +54,7 @@ typedef struct fsl_i2c {
 #define I2C_CR_MTX	0x10
 #define I2C_CR_TXAK	0x08
 #define I2C_CR_RSTA	0x04
+#define I2C_CR_BIT6	0x02	/* required for workaround A004447 */
 #define I2C_CR_BCST	0x01
 
 	u8 sr;		/* I2C status register */

arch/powerpc/include/asm/processor.h

@@ -847,7 +847,7 @@
 /* System-On-Chip Version Register (SVR) field extraction */
 
 #define SVR_VER(svr)	(((svr) >> 16) & 0xFFFF) /* Version field */
-#define SVR_REV(svr)	(((svr) >>  0) & 0xFFFF) /* Revision field */
+#define SVR_REV(svr)	(((svr) >>  0) & 0xFF)	 /* Revision field */
 
 #define SVR_CID(svr)	(((svr) >> 28) & 0x0F)	 /* Company or manufacturer ID */
 #define SVR_SOCOP(svr)	(((svr) >> 22) & 0x3F)	 /* SOC integration options */
@@ -1043,9 +1043,6 @@
 
 /* System Version Register (SVR) field extraction */
 
-#define SVR_VER(svr)	(((svr) >>  16) & 0xFFFF)	/* Version field */
-#define SVR_REV(svr)	(((svr) >>   0) & 0xFFFF)	/* Revison field */
-
 #define SVR_SUBVER(svr)	(((svr) >>  8) & 0xFF)	/* Process/MFG sub-version */
 
 #define SVR_FAM(svr)	(((svr) >> 20) & 0xFFF)	/* Family field */

drivers/i2c/fsl_i2c.c

@@ -211,6 +211,14 @@ static int fsl_i2c_fixup(const struct fsl_i2c *dev)
 	const unsigned long long timeout = usec2ticks(CONFIG_I2C_MBB_TIMEOUT);
 	unsigned long long timeval = 0;
 	int ret = -1;
+	unsigned int flags = 0;
+
+#ifdef CONFIG_SYS_FSL_ERRATUM_I2C_A004447
+	unsigned int svr = get_svr();
+	if ((SVR_SOC_VER(svr) == SVR_8548 && IS_SVR_REV(svr, 3, 1)) ||
+	    (SVR_REV(svr) <= CONFIG_SYS_FSL_A004447_SVR_REV))
+		flags = I2C_CR_BIT6;
+#endif
 
 	writeb(I2C_CR_MEN | I2C_CR_MSTA, &dev->cr);
 
@@ -224,8 +232,8 @@ static int fsl_i2c_fixup(const struct fsl_i2c *dev)
 		/* SDA is stuck low */
 		writeb(0, &dev->cr);
 		udelay(100);
-		writeb(I2C_CR_MSTA, &dev->cr);
-		writeb(I2C_CR_MEN | I2C_CR_MSTA, &dev->cr);
+		writeb(I2C_CR_MSTA | flags, &dev->cr);
+		writeb(I2C_CR_MEN | I2C_CR_MSTA | flags, &dev->cr);
 	}
 
 	readb(&dev->dr);
@@ -238,7 +246,7 @@ static int fsl_i2c_fixup(const struct fsl_i2c *dev)
 	ret = 0;
 
 err:
-	writeb(I2C_CR_MEN, &dev->cr);
+	writeb(I2C_CR_MEN | flags, &dev->cr);
 	writeb(0, &dev->sr);
 	udelay(100);