From 28f0cbcdd28c03c44d867a6641d642e97d4704a8 Mon Sep 17 00:00:00 2001 From: Joshua Scott Date: Mon, 9 Nov 2020 10:14:08 +1300 Subject: [PATCH] arm: mvebu: a38x: Configurable USB2 high-speed impedance threshold Hardware testing of a board using the Armada 385 has shown that an impedance threshold setting of 0x7 performs better in an eye-diagram test than with Marvell's recommended value 0x6. As other boards may still perform better with Marvell's reccomended value, a configuration option is added with a default value of 0x6. Signed-off-by: Joshua Scott Reviewed-by: Stefan Roese --- arch/arm/mach-mvebu/Kconfig | 6 ++++++ arch/arm/mach-mvebu/serdes/a38x/high_speed_env_spec.c | 6 +++--- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/arm/mach-mvebu/Kconfig b/arch/arm/mach-mvebu/Kconfig index 0d8e0922a2..72aee8b3e5 100644 --- a/arch/arm/mach-mvebu/Kconfig +++ b/arch/arm/mach-mvebu/Kconfig @@ -30,6 +30,12 @@ config ARMADA_38X select ARMADA_32BIT select HAVE_MVEBU_EFUSE +config ARMADA_38X_HS_IMPEDANCE_THRESH + hex "Armada 38x USB 2.0 High-Speed Impedance Threshold (0x0 - 0x7)" + depends on ARMADA_38X + default 0x6 + range 0x0 0x7 + config ARMADA_XP bool select ARMADA_32BIT diff --git a/arch/arm/mach-mvebu/serdes/a38x/high_speed_env_spec.c b/arch/arm/mach-mvebu/serdes/a38x/high_speed_env_spec.c index 2454730e6d..ae2a361104 100644 --- a/arch/arm/mach-mvebu/serdes/a38x/high_speed_env_spec.c +++ b/arch/arm/mach-mvebu/serdes/a38x/high_speed_env_spec.c @@ -677,9 +677,9 @@ struct op_params usb2_power_up_params[] = { {0xc200c, 0x0 /*NA*/, 0xf000, {0x1000}, 0, 0}, {0xc400c, 0x0 /*NA*/, 0xf000, {0x1000}, 0, 0}, /* Change the High speed impedance threshold */ - {0xc0008, 0x0 /*NA*/, 0x700, {0x600}, 0, 0}, - {0xc2008, 0x0 /*NA*/, 0x700, {0x600}, 0, 0}, - {0xc4008, 0x0 /*NA*/, 0x700, {0x600}, 0, 0}, + {0xc0008, 0x0 /*NA*/, 0x700, {CONFIG_ARMADA_38X_HS_IMPEDANCE_THRESH << 8}, 0, 0}, + {0xc2008, 0x0 /*NA*/, 0x700, {CONFIG_ARMADA_38X_HS_IMPEDANCE_THRESH << 8}, 0, 0}, + {0xc4008, 0x0 /*NA*/, 0x700, {CONFIG_ARMADA_38X_HS_IMPEDANCE_THRESH << 8}, 0, 0}, /* Change the squelch level of the receiver to meet the receiver electrical measurements (squelch and receiver sensitivity tests) */ {0xc0014, 0x0 /*NA*/, 0xf, {0x8}, 0, 0}, {0xc2014, 0x0 /*NA*/, 0xf, {0x8}, 0, 0}, -- 2.39.5