[U-Boot] [PATCH 3/3] ARM: DRA74-evm: Use SMA_1 spare register to workaround DP83865 phy on SR2.0

[Nishanth Menon <nm@ti.com>]

DP83865 ethernet phy used on DRA74x-evm is quirky and the datasheet
provided IODELAY values for standard RGMII phys do not work.

Silicon Revision(SR) 2.0 provides an alternative bit configuration
that allows us to do a "gross adjustment" to launch the data off a
different internal clock edge. Manual IO Delay overrides are still
necessary to fine tune the clock-to-data delays. This is a necessary
workaround for the quirky ethernet Phy we have on the platform.

NOTE: SMA registers are spare "kitchen sink" registers that does
contain bits for other workaround as necessary as well. Hence the
control for the same is introduced in a generic SoC specific, board
generic location.

Signed-off-by: Nishanth Menon <nm@ti.com>
---
 arch/arm/cpu/armv7/omap5/prcm-regs.c             | 9 +++++++++
 arch/arm/include/asm/arch-omap5/dra7xx_iodelay.h | 4 ++++
 arch/arm/include/asm/arch-omap5/omap.h           | 2 ++
 arch/arm/include/asm/omap_common.h               | 1 +
 board/ti/dra7xx/evm.c                            | 3 +++
 5 files changed, 19 insertions(+)

diff --git a/arch/arm/cpu/armv7/omap5/prcm-regs.c b/arch/arm/cpu/armv7/omap5/prcm-regs.c
index cd51fe7678be..251e0af9fc6f 100644
--- a/arch/arm/cpu/armv7/omap5/prcm-regs.c
+++ b/arch/arm/cpu/armv7/omap5/prcm-regs.c
@@ -11,6 +11,7 @@
  */
 
 #include <asm/omap_common.h>
+#include <asm/io.h>
 
 struct prcm_regs const omap5_es1_prcm = {
 	/* cm1.ckgen */
@@ -379,6 +380,7 @@ struct omap_sys_ctrl_regs const dra7xx_ctrl = {
 	.control_phy_power_usb			= 0x4A002370,
 	.control_phy_power_sata			= 0x4A002374,
 	.ctrl_core_sma_sw_0			= 0x4A0023FC,
+	.ctrl_core_sma_sw_1			= 0x4A002534,
 	.control_core_mac_id_0_lo		= 0x4A002514,
 	.control_core_mac_id_0_hi		= 0x4A002518,
 	.control_core_mac_id_1_lo		= 0x4A00251C,
@@ -990,3 +992,10 @@ struct prcm_regs const dra7xx_prcm = {
 	.prm_abbldo_mpu_setup			= 0x4AE07DDC,
 	.prm_abbldo_mpu_ctrl			= 0x4AE07DE0,
 };
+
+void clrset_spare_register(u8 spare_type, u32 clear_bits, u32 set_bits)
+{
+	u32 reg = spare_type ? (*ctrl)->ctrl_core_sma_sw_1 :
+		(*ctrl)->ctrl_core_sma_sw_0;
+	clrsetbits_le32(reg, clear_bits, set_bits);
+}
diff --git a/arch/arm/include/asm/arch-omap5/dra7xx_iodelay.h b/arch/arm/include/asm/arch-omap5/dra7xx_iodelay.h
index 2f53d85283b8..4cd0a3cc80d0 100644
--- a/arch/arm/include/asm/arch-omap5/dra7xx_iodelay.h
+++ b/arch/arm/include/asm/arch-omap5/dra7xx_iodelay.h
@@ -49,6 +49,10 @@
 #define ISOLATE_IO			1
 #define DEISOLATE_IO			0
 
+/* CTRL_CORE_SMA_SW_1 */
+#define RGMII2_ID_MODE_N_MASK		(1 << 26)
+#define RGMII1_ID_MODE_N_MASK		(1 << 25)
+
 /* PRM_IO_PMCTRL */
 #define PMCTRL_ISOCLK_OVERRIDE_SHIFT	0
 #define PMCTRL_ISOCLK_OVERRIDE_MASK	(1 << 0)
diff --git a/arch/arm/include/asm/arch-omap5/omap.h b/arch/arm/include/asm/arch-omap5/omap.h
index ddf5c7a8eae7..c3296412adeb 100644
--- a/arch/arm/include/asm/arch-omap5/omap.h
+++ b/arch/arm/include/asm/arch-omap5/omap.h
@@ -235,6 +235,8 @@ struct ctrl_ioregs {
 	u32 ctrl_ddr_ctrl_ext_0;
 };
 
+void clrset_spare_register(u8 spare_type, u32 clear_bits, u32 set_bits);
+
 #endif /* __ASSEMBLY__ */
 
 /* Boot parameters */
diff --git a/arch/arm/include/asm/omap_common.h b/arch/arm/include/asm/omap_common.h
index 2f2001d3253f..7be29a682ba0 100644
--- a/arch/arm/include/asm/omap_common.h
+++ b/arch/arm/include/asm/omap_common.h
@@ -462,6 +462,7 @@ struct omap_sys_ctrl_regs {
 	u32 control_padconf_wkup_base;
 	u32 iodelay_config_base;
 	u32 ctrl_core_sma_sw_0;
+	u32 ctrl_core_sma_sw_1;
 };
 
 struct dpll_params {
diff --git a/board/ti/dra7xx/evm.c b/board/ti/dra7xx/evm.c
index 9603f10f8ade..6e3c85513f89 100644
--- a/board/ti/dra7xx/evm.c
+++ b/board/ti/dra7xx/evm.c
@@ -104,6 +104,9 @@ void recalibrate_iodelay(void)
 		npads = ARRAY_SIZE(dra74x_core_padconf_array);
 		iodelay = dra742_es2_0_iodelay_cfg_array;
 		niodelays = ARRAY_SIZE(dra742_es2_0_iodelay_cfg_array);
+		/* Setup port1 and port2 for rgmii with 'no-id' mode */
+		clrset_spare_register(1, 0, RGMII2_ID_MODE_N_MASK |
+				      RGMII1_ID_MODE_N_MASK);
 		break;
 	}
 	__recalibrate_iodelay(pads, npads, iodelay, niodelays);
-- 
2.1.4