diff options
Diffstat (limited to 'board/cr50/ap_state.c')
| -rw-r--r-- | board/cr50/ap_state.c | 205 |
1 files changed, 0 insertions, 205 deletions
diff --git a/board/cr50/ap_state.c b/board/cr50/ap_state.c deleted file mode 100644 index 1224818f5b..0000000000 --- a/board/cr50/ap_state.c +++ /dev/null @@ -1,205 +0,0 @@ -/* Copyright 2017 The Chromium OS Authors. All rights reserved. - * Use of this source code is governed by a BSD-style license that can be - * found in the LICENSE file. - * - * AP state machine - */ -#include "ec_commands.h" -#include "gpio.h" -#include "hooks.h" -#include "registers.h" -#include "system.h" -#include "tpm_registers.h" - -#define CPRINTS(format, args...) cprints(CC_SYSTEM, format, ## args) - -static enum device_state state = DEVICE_STATE_INIT; - -void print_ap_state(void) -{ - ccprintf("AP: %s\n", device_state_name(state)); -} - -int ap_is_on(void) -{ - return state == DEVICE_STATE_ON; -} - -/** - * Set the AP state. - * - * Done as a function to make it easier to debug state transitions. Note that - * this ONLY sets the state (and possibly prints debug info), and doesn't do - * all the additional transition work that set_ap_on(), etc. do. - * - * @param new_state State to set. - */ -static void set_state(enum device_state new_state) -{ -#ifdef CR50_DEBUG_AP_STATE - /* Print all state transitions. May spam the console. */ - if (state != new_state) - CPRINTS("AP %s -> %s", - device_state_name(state), device_state_name(new_state)); -#endif - state = new_state; -} - -/** - * Set AP to the off state. Disable functionality that should only be available - * when the AP is on. - */ -static void deferred_set_ap_off(void) -{ - CPRINTS("AP off"); - set_state(DEVICE_STATE_OFF); - - /* - * If TPM is configured then the INT_AP_L signal is used as a low pulse - * trigger to sync transactions with the host. By default Cr50 is - * driving this line high, but when the AP powers off, the 1.8V rail - * that it's pulled up to will be off and cause excessive power to be - * consumed by the Cr50. Set INT_AP_L as an input while the AP is - * powered off. - */ - gpio_set_flags(GPIO_INT_AP_L, GPIO_INPUT); - - ccd_update_state(); - - /* - * We don't enable deep sleep on ARM devices yet, as its processing - * there will require more support on the AP side than is available - * now. - * - * Note: Presence of platform reset is a poor indicator of deep sleep - * support. It happens to be correlated with ARM vs x86 at present. - */ - if (board_deep_sleep_allowed()) - enable_deep_sleep(); -} -DECLARE_DEFERRED(deferred_set_ap_off); - -/** - * Move the AP to the ON state - */ -void set_ap_on(void) -{ - hook_call_deferred(&deferred_set_ap_off_data, -1); - CPRINTS("AP on"); - set_state(DEVICE_STATE_ON); - - /* - * AP is powering up, set the host sync signal to output and set it - * high which is the default level. - */ - gpio_set_flags(GPIO_INT_AP_L, GPIO_OUT_HIGH); - gpio_set_level(GPIO_INT_AP_L, 1); - - ccd_update_state(); - - if (board_deep_sleep_allowed()) - disable_deep_sleep(); -} - -static uint8_t waiting_for_ap_reset; -/* - * If TPM_RST_L is asserted, the AP is in reset. Disable all AP functionality - * in 1 second if it remains asserted. - */ -void tpm_rst_asserted(enum gpio_signal unused) -{ - CPRINTS("%s", __func__); - - /* - * It's possible the signal is being pulsed. Wait 1 second to disable - * functionality, so it's more likely the AP is fully off and not being - * reset. - */ - hook_call_deferred(&deferred_set_ap_off_data, SECOND); - - set_state(DEVICE_STATE_DEBOUNCING); - - if (waiting_for_ap_reset) { - CPRINTS("CL: done"); - waiting_for_ap_reset = 0; - deassert_ec_rst(); - enable_sleep(SLEEP_MASK_AP_RUN); - } -} - -void board_closed_loop_reset(void) -{ - CPRINTS("CL: start"); - /* Disable sleep while waiting for the reset */ - disable_sleep(SLEEP_MASK_AP_RUN); - - /* Until the AP resets, we can't trust it's state */ - set_state(DEVICE_STATE_UNKNOWN); - - waiting_for_ap_reset = 1; - - /* Disable AP communications with the TPM until cr50 sees the reset */ - tpm_stop(); - - /* Use EC_RST_L to reset the system */ - assert_ec_rst(); - - /* - * DETECT_TPM_RST_L_ASSERTED is edge triggered. If TPM_RST_L is already - * low, tpm_rst_asserted wont get called. Alert tpm_rst_asserted - * manually if the signal is already low. - */ - if (!gpio_get_level(GPIO_DETECT_TPM_RST_L_ASSERTED)) - tpm_rst_asserted(GPIO_TPM_RST_L); -} - -/** - * Check the initial AP state. - */ -static void init_ap_detect(void) -{ - /* Enable interrupts for AP state detection */ - gpio_enable_interrupt(GPIO_TPM_RST_L); - gpio_enable_interrupt(GPIO_DETECT_TPM_RST_L_ASSERTED); - /* - * After resuming from any reset other than deep sleep, cr50 needs to - * make sure the rest of the system has reset. If cr50 needs a closed - * loop reset to reset the system, it can't rely on the short EC_RST - * pulse from RO. Use the closed loop reset to ensure the system has - * actually been reset. - * - * During this reset, the ap state will not be set to 'on' until the AP - * enters and then leaves reset. The tpm waits until the ap is on before - * allowing any tpm activity, so it wont do anything until the reset is - * complete. - */ - if (board_uses_closed_loop_reset() && - !(system_get_reset_flags() & EC_RESET_FLAG_HIBERNATE)) { - board_closed_loop_reset(); - } else { - /* - * If the TPM_RST_L signal is already high when cr50 wakes up or - * transitions to high before we are able to configure the gpio - * then we will have missed the edge and the tpm reset isr will - * not get called. Check that we haven't already missed the - * rising edge. If we have alert tpm_rst_isr. - * - * DONT alert tpm_rst_isr if the board is waiting for the closed - * loop reset to finish. The isr is edge triggered, so - * tpm_rst_deasserted wont be called until the AP enters and - * exits reset. That is what we want. The TPM and other - * peripherals check ap_is_on before enabling interactions with - * the AP, and we want these to be disabled until the closed - * loop reset is complete. - */ - if (gpio_get_level(GPIO_TPM_RST_L)) - tpm_rst_deasserted(GPIO_TPM_RST_L); - else - tpm_rst_asserted(GPIO_TPM_RST_L); - } -} -/* - * TPM_RST_L isn't setup until board_init. Make sure init_ap_detect happens - * after that. - */ -DECLARE_HOOK(HOOK_INIT, init_ap_detect, HOOK_PRIO_DEFAULT + 1); |