[U-Boot] [PATCH u-boot sunxi 10/12] sunxi: fast MBUS support on sun7i

[Hans de Goede]

From: Emilio López <emilio at elopez.com.ar>

For qualifying hardware, we can run MBUS at 400MHz without risking
stability if we raise the DCDC3 voltage to 1.3V .

This is desirable since on A20 the MBUS is a significant bottle-neck
for some workloads.

This has been tested on 50 pieces of Cubieboard2 by Cubietech and no
issues of any kind were reported.

Signed-off-by: Emilio López <emilio at elopez.com.ar>
Signed-off-by: Hans de Goede <hdegoede at redhat.com>
---
 arch/arm/cpu/armv7/sunxi/dram.c | 6 +++++-
 board/sunxi/board.c             | 4 ++++
 boards.cfg                      | 4 ++--
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/arch/arm/cpu/armv7/sunxi/dram.c b/arch/arm/cpu/armv7/sunxi/dram.c
index 781f9b5..9061f98 100644
--- a/arch/arm/cpu/armv7/sunxi/dram.c
+++ b/arch/arm/cpu/armv7/sunxi/dram.c
@@ -217,7 +217,11 @@ static void mctl_setup_dram_clock(u32 clk)
 
 	/* setup MBUS clock */
 	reg_val = CCM_MBUS_CTRL_GATE |
-#if defined(CONFIG_SUN7I)
+#if defined(CONFIG_SUN7I) && defined(CONFIG_FAST_MBUS)
+		  CCM_MBUS_CTRL_CLK_SRC(CCM_MBUS_CTRL_CLK_SRC_PLL6) |
+		  CCM_MBUS_CTRL_N(CCM_MBUS_CTRL_N_X(1)) |
+		  CCM_MBUS_CTRL_M(CCM_MBUS_CTRL_M_X(3));
+#elif defined(CONFIG_SUN7I) && !defined(CONFIG_FAST_MBUS)
 		  CCM_MBUS_CTRL_CLK_SRC(CCM_MBUS_CTRL_CLK_SRC_PLL6) |
 		  CCM_MBUS_CTRL_N(CCM_MBUS_CTRL_N_X(2)) |
 		  CCM_MBUS_CTRL_M(CCM_MBUS_CTRL_M_X(2));
diff --git a/board/sunxi/board.c b/board/sunxi/board.c
index e9801b9..4dadf2b 100644
--- a/board/sunxi/board.c
+++ b/board/sunxi/board.c
@@ -84,7 +84,11 @@ void sunxi_board_init(void)
 #ifdef CONFIG_AXP209_POWER
 	power_failed |= axp209_init();
 	power_failed |= axp209_set_dcdc2(1400);
+#ifdef CONFIG_FAST_MBUS
+	power_failed |= axp209_set_dcdc3(1300);
+#else
 	power_failed |= axp209_set_dcdc3(1250);
+#endif
 	power_failed |= axp209_set_ldo2(3000);
 	power_failed |= axp209_set_ldo3(2800);
 	power_failed |= axp209_set_ldo4(2800);
diff --git a/boards.cfg b/boards.cfg
index 20f7510..82d2c6a 100644
--- a/boards.cfg
+++ b/boards.cfg
@@ -355,8 +355,8 @@ Active  arm         armv7          s5pc1xx     samsung         smdkc100
 Active  arm         armv7          socfpga     altera          socfpga             socfpga_cyclone5                     -                                                                                                                                 -
 Active  arm         armv7          sunxi       -               sunxi               A10-OLinuXino-Lime                   sun4i:A10_OLINUXINO_L,AXP209_POWER,SPL                                                                                            -
 Active  arm         armv7          sunxi       -               sunxi               A10s-OLinuXino-M                     sun5i:A10S_OLINUXINO_M,AXP152_POWER,SPL                                                                                           -
-Active  arm         armv7          sunxi       -               sunxi               Cubietruck                           sun7i:CUBIETRUCK,AXP209_POWER,SPL                                                                                                 -
-Active  arm         armv7          sunxi       -               sunxi               Cubietruck_FEL                       sun7i:CUBIETRUCK,AXP209_POWER,SPL_FEL                                                                                             -
+Active  arm         armv7          sunxi       -               sunxi               Cubietruck                           sun7i:CUBIETRUCK,AXP209_POWER,FAST_MBUS,SPL                                                                                       -
+Active  arm         armv7          sunxi       -               sunxi               Cubietruck_FEL                       sun7i:CUBIETRUCK,AXP209_POWER,FAST_MBUS,SPL_FEL                                                                                   -
 Active  arm         armv7          u8500       st-ericsson     snowball            snowball                             -                                                                                                                                 Mathieu Poirier <mathieu.poirier at linaro.org>
 Active  arm         armv7          u8500       st-ericsson     u8500               u8500_href                           -                                                                                                                                 -
 Active  arm         armv7          vf610       freescale       vf610twr            vf610twr                             vf610twr:IMX_CONFIG=board/freescale/vf610twr/imximage.cfg                                                                         Alison Wang <b18965 at freescale.com>
-- 
1.9.0