powerpc/usb: Workaround for erratum-A006261

USB spec says that the minimum disconnect threshold should be
	over 525 mV. However, internal USB PHY threshold value is below
	this specified value. Due to this some devices disconnect at
	run-time. Hence, phy settings are tweaked to increased disconnect
	threshold to be above 525mV by using this workaround.

Signed-off-by: Suresh Gupta <suresh.gupta@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>

2 files changed, 66 insertions, 0 deletions

diff --git a/arch/powerpc/cpu/mpc85xx/cmd_errata.c b/arch/powerpc/cpu/mpc85xx/cmd_errata.c
index d0a1c518bb..8b79c05b1f 100644
--- a/arch/powerpc/cpu/mpc85xx/cmd_errata.c
+++ b/arch/powerpc/cpu/mpc85xx/cmd_errata.c
@@ -273,6 +273,10 @@ static int do_errata(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	    (SVR_REV(svr) <= CONFIG_SYS_FSL_A004447_SVR_REV))
 		puts("Work-around for Erratum I2C-A004447 enabled\n");
 #endif
+#ifdef CONFIG_SYS_FSL_ERRATUM_A006261
+	if (has_erratum_a006261())
+		puts("Work-around for Erratum A006261 enabled\n");
+#endif
 	return 0;
 }
 
diff --git a/arch/powerpc/cpu/mpc85xx/cpu_init.c b/arch/powerpc/cpu/mpc85xx/cpu_init.c
index b31efb7610..81aeadd363 100644
--- a/arch/powerpc/cpu/mpc85xx/cpu_init.c
+++ b/arch/powerpc/cpu/mpc85xx/cpu_init.c
@@ -36,6 +36,54 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+#ifdef CONFIG_SYS_FSL_ERRATUM_A006261
+void fsl_erratum_a006261_workaround(struct ccsr_usb_phy __iomem *usb_phy)
+{
+#ifdef CONFIG_SYS_FSL_USB_DUAL_PHY_ENABLE
+	u32 xcvrprg = in_be32(&usb_phy->port1.xcvrprg);
+
+	/* Increase Disconnect Threshold by 50mV */
+	xcvrprg &= ~CONFIG_SYS_FSL_USB_XCVRPRG_HS_DCNT_PROG_MASK |
+						INC_DCNT_THRESHOLD_50MV;
+	/* Enable programming of USB High speed Disconnect threshold */
+	xcvrprg |= CONFIG_SYS_FSL_USB_XCVRPRG_HS_DCNT_PROG_EN;
+	out_be32(&usb_phy->port1.xcvrprg, xcvrprg);
+
+	xcvrprg = in_be32(&usb_phy->port2.xcvrprg);
+	/* Increase Disconnect Threshold by 50mV */
+	xcvrprg &= ~CONFIG_SYS_FSL_USB_XCVRPRG_HS_DCNT_PROG_MASK |
+						INC_DCNT_THRESHOLD_50MV;
+	/* Enable programming of USB High speed Disconnect threshold */
+	xcvrprg |= CONFIG_SYS_FSL_USB_XCVRPRG_HS_DCNT_PROG_EN;
+	out_be32(&usb_phy->port2.xcvrprg, xcvrprg);
+#else
+
+	u32 temp = 0;
+	u32 status = in_be32(&usb_phy->status1);
+
+	u32 squelch_prog_rd_0_2 =
+		(status >> CONFIG_SYS_FSL_USB_SQUELCH_PROG_RD_0)
+			& CONFIG_SYS_FSL_USB_SQUELCH_PROG_MASK;
+
+	u32 squelch_prog_rd_3_5 =
+		(status >> CONFIG_SYS_FSL_USB_SQUELCH_PROG_RD_3)
+			& CONFIG_SYS_FSL_USB_SQUELCH_PROG_MASK;
+
+	setbits_be32(&usb_phy->config1,
+		     CONFIG_SYS_FSL_USB_HS_DISCNCT_INC);
+	setbits_be32(&usb_phy->config2,
+		     CONFIG_SYS_FSL_USB_RX_AUTO_CAL_RD_WR_SEL);
+
+	temp = squelch_prog_rd_0_2 << CONFIG_SYS_FSL_USB_SQUELCH_PROG_WR_0;
+	out_be32(&usb_phy->config2, in_be32(&usb_phy->config2) | temp);
+
+	temp = squelch_prog_rd_3_5 << CONFIG_SYS_FSL_USB_SQUELCH_PROG_WR_3;
+	out_be32(&usb_phy->config2, in_be32(&usb_phy->config2) | temp);
+#endif
+}
+#endif
+
+
 #ifdef CONFIG_QE
 extern qe_iop_conf_t qe_iop_conf_tab[];
 extern void qe_config_iopin(u8 port, u8 pin, int dir,
@@ -625,6 +673,10 @@ skip_l2:
 	{
 		struct ccsr_usb_phy __iomem *usb_phy1 =
 			(void *)CONFIG_SYS_MPC85xx_USB1_PHY_ADDR;
+#ifdef CONFIG_SYS_FSL_ERRATUM_A006261
+		if (has_erratum_a006261())
+			fsl_erratum_a006261_workaround(usb_phy1);
+#endif
 		out_be32(&usb_phy1->usb_enable_override,
 				CONFIG_SYS_FSL_USB_ENABLE_OVERRIDE);
 	}
@@ -633,6 +685,10 @@ skip_l2:
 	{
 		struct ccsr_usb_phy __iomem *usb_phy2 =
 			(void *)CONFIG_SYS_MPC85xx_USB2_PHY_ADDR;
+#ifdef CONFIG_SYS_FSL_ERRATUM_A006261
+		if (has_erratum_a006261())
+			fsl_erratum_a006261_workaround(usb_phy2);
+#endif
 		out_be32(&usb_phy2->usb_enable_override,
 				CONFIG_SYS_FSL_USB_ENABLE_OVERRIDE);
 	}
@@ -672,8 +728,14 @@ skip_l2:
 			     CONFIG_SYS_FSL_USB_DRVVBUS_CR_EN);
 		setbits_be32(&usb_phy->port2.pwrfltcfg,
 			     CONFIG_SYS_FSL_USB_PWRFLT_CR_EN);
+
+#ifdef CONFIG_SYS_FSL_ERRATUM_A006261
+		if (has_erratum_a006261())
+			fsl_erratum_a006261_workaround(usb_phy);
 #endif
 
+#endif /* CONFIG_SYS_FSL_USB_DUAL_PHY_ENABLE */
+
 #ifdef CONFIG_FMAN_ENET
 	fman_enet_init();
 #endif