From d086e3d6e42036b1ec0fc2173db5386279ac838b Mon Sep 17 00:00:00 2001 From: Karthikeyan Ramasubramanian Date: Fri, 8 Oct 2021 17:04:10 -0600 Subject: [PATCH] mb/google/guybrush: Assert WWAN_AUX_RST_L on S0i3 entry Currently WWAN_AUX_RST_L is in S5 domain and does not get asserted on S0i3 entry. Based on the schematics, the pull-down on that signal leads to 10 mW power leakage on S0i3 entry. Assert the signal on S0i3 entry to achieve some power savings and de-assert it on S0i3 exit. BUG=b:195748540 TEST=Build and boot to OS in Guybrush. Ensure that the signal gets asserted on S0i3 entry and de-asserted on S0i3 exit. Trigger suspend/resume cycles and ensure that the WWAN module is enumerated after each cycle. Change-Id: I43c8655ee5209779748e4365db973e094cb08aca Signed-off-by: Karthikeyan Ramasubramanian Reviewed-on: https://review.coreboot.org/c/coreboot/+/58275 Reviewed-by: Raul Rangel Tested-by: build bot (Jenkins) --- src/mainboard/google/guybrush/mainboard.c | 28 +++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/src/mainboard/google/guybrush/mainboard.c b/src/mainboard/google/guybrush/mainboard.c index 3626157338..39ef2a0795 100644 --- a/src/mainboard/google/guybrush/mainboard.c +++ b/src/mainboard/google/guybrush/mainboard.c @@ -13,11 +13,13 @@ #include #define BACKLIGHT_GPIO GPIO_129 +#define WWAN_AUX_RST_GPIO GPIO_18 #define METHOD_BACKLIGHT_ENABLE "\\_SB.BKEN" #define METHOD_BACKLIGHT_DISABLE "\\_SB.BKDS" #define METHOD_MAINBOARD_INI "\\_SB.MINI" #define METHOD_MAINBOARD_WAK "\\_SB.MWAK" #define METHOD_MAINBOARD_PTS "\\_SB.MPTS" +#define METHOD_MAINBOARD_S0X "\\_SB.MS0X" /* * These arrays set up the FCH PCI_INTR registers 0xC00/0xC01. @@ -151,6 +153,31 @@ static void mainboard_write_mpts(void) acpigen_pop_len(); } +static void mainboard_assert_wwan_aux_reset(void) +{ + if (variant_has_pcie_wwan()) + acpigen_soc_clear_tx_gpio(WWAN_AUX_RST_GPIO); +} + +static void mainboard_deassert_wwan_aux_reset(void) +{ + if (variant_has_pcie_wwan()) + acpigen_soc_set_tx_gpio(WWAN_AUX_RST_GPIO); +} + +static void mainboard_write_ms0x(void) +{ + acpigen_write_method_serialized(METHOD_MAINBOARD_S0X, 1); + /* S0ix Entry */ + acpigen_write_if_lequal_op_int(ARG0_OP, 1); + mainboard_assert_wwan_aux_reset(); + /* S0ix Exit */ + acpigen_write_else(); + mainboard_deassert_wwan_aux_reset(); + acpigen_pop_len(); + acpigen_pop_len(); +} + static void mainboard_fill_ssdt(const struct device *dev) { mainboard_write_blken(); @@ -158,6 +185,7 @@ static void mainboard_fill_ssdt(const struct device *dev) mainboard_write_mini(); mainboard_write_mpts(); mainboard_write_mwak(); + mainboard_write_ms0x(); } static void mainboard_enable(struct device *dev)