From a76e6542d1ab39ca50777f3fd0146151d0868c5c Mon Sep 17 00:00:00 2001 From: Tristan Shieh Date: Mon, 8 Apr 2019 11:01:40 +0800 Subject: [PATCH] mediatek: Use the 64-bit timer GPT4 is a 32-bit timer and the counter of GPT4 will overflow in about 330 seconds (0xffffffff / 13MHz). Timer and delay functions will not work properly if the counter overflows. To fix that we should use the 64-bit timer (GPT6). BUG=b:80501386 BRANCH=none Test=emerge-elm coreboot; emerge-kukui coreboot Change-Id: I9f080e47253a1b1bab4636a45cb86c8666a25302 Signed-off-by: Tristan Shieh Reviewed-on: https://review.coreboot.org/c/coreboot/+/32245 Tested-by: build bot (Jenkins) Reviewed-by: Hung-Te Lin Reviewed-by: Julius Werner Reviewed-by: You-Cheng Syu --- payloads/libpayload/drivers/timer/Kconfig | 5 ++-- src/soc/mediatek/common/include/soc/timer.h | 19 +++++++++------ src/soc/mediatek/common/timer.c | 27 +++++++++++++++------ src/soc/mediatek/mt8173/timer.c | 2 +- 4 files changed, 35 insertions(+), 18 deletions(-) diff --git a/payloads/libpayload/drivers/timer/Kconfig b/payloads/libpayload/drivers/timer/Kconfig index f1542cf9db..5a61dfab51 100644 --- a/payloads/libpayload/drivers/timer/Kconfig +++ b/payloads/libpayload/drivers/timer/Kconfig @@ -54,7 +54,7 @@ config TIMER_IMG_PISTACHIO bool "Timer for IMG Pistachio" config TIMER_MTK - bool "Timer for MediaTek MT8173" + bool "Timer for MediaTek" endchoice @@ -77,7 +77,7 @@ config TIMER_GENERIC_REG default 0x004A2000 if TIMER_IPQ40XX default 0x0200A028 if TIMER_IPQ806X default 0x101C0100 if TIMER_MCT - default 0x10008048 if TIMER_MTK + default 0x10008068 if TIMER_MTK default 0xff810028 if TIMER_RK3288 default 0xff850008 if TIMER_RK3399 default 0x60005010 if TIMER_TEGRA_1US @@ -89,6 +89,7 @@ config TIMER_GENERIC_HIGH_REG hex "Generic Timer High Register Address" default 0x004A2004 if TIMER_IPQ40XX default 0x101C0104 if TIMER_MCT + default 0x10008078 if TIMER_MTK default 0xff81002C if TIMER_RK3288 default 0xff85000C if TIMER_RK3399 default 0x0 diff --git a/src/soc/mediatek/common/include/soc/timer.h b/src/soc/mediatek/common/include/soc/timer.h index babcbba561..b58d4d3227 100644 --- a/src/soc/mediatek/common/include/soc/timer.h +++ b/src/soc/mediatek/common/include/soc/timer.h @@ -19,18 +19,21 @@ #include #include -#define GPT4_MHZ 13 +#define GPT_MHZ 13 struct mtk_gpt_regs { - u32 reserved[16]; - u32 gpt4_con; - u32 gpt4_clk; - u32 gpt4_cnt; + u32 reserved1[24]; + u32 gpt6_con; + u32 gpt6_clk; + u32 gpt6_cnt_l; + u32 reserved2[3]; + u32 gpt6_cnt_h; }; -check_member(mtk_gpt_regs, gpt4_con, 0x0040); -check_member(mtk_gpt_regs, gpt4_clk, 0x0044); -check_member(mtk_gpt_regs, gpt4_cnt, 0x0048); +check_member(mtk_gpt_regs, gpt6_con, 0x0060); +check_member(mtk_gpt_regs, gpt6_clk, 0x0064); +check_member(mtk_gpt_regs, gpt6_cnt_l, 0x0068); +check_member(mtk_gpt_regs, gpt6_cnt_h, 0x0078); enum { GPT_CON_EN = 0x01, diff --git a/src/soc/mediatek/common/timer.c b/src/soc/mediatek/common/timer.c index 0762c2b4b4..c8af2be113 100644 --- a/src/soc/mediatek/common/timer.c +++ b/src/soc/mediatek/common/timer.c @@ -25,21 +25,34 @@ static struct mtk_gpt_regs *const mtk_gpt = (void *)GPT_BASE; __weak void timer_prepare(void) { /* do nothing */ } +static uint64_t timer_raw_value(void) +{ + /* + * According to "General-Purpose Timer (GPT).pdf", The read operation of + * gpt6_cnt_l will make gpt6_cnt_h fixed until the next read operation + * of gpt6_cnt_l. Therefore, we must read gpt6_cnt_l before gpt6_cnt_h. + */ + uint32_t low = read32(&mtk_gpt->gpt6_cnt_l); + uint32_t high = read32(&mtk_gpt->gpt6_cnt_h); + + return low | (uint64_t)high << 32; +} + void timer_monotonic_get(struct mono_time *mt) { - mono_time_set_usecs(mt, read32(&mtk_gpt->gpt4_cnt) / GPT4_MHZ); + mono_time_set_usecs(mt, timer_raw_value() / GPT_MHZ); } void init_timer(void) { timer_prepare(); - /* Disable GPT4 and clear the counter */ - clrbits_le32(&mtk_gpt->gpt4_con, GPT_CON_EN); - setbits_le32(&mtk_gpt->gpt4_con, GPT_CON_CLR); + /* Disable timer and clear the counter */ + clrbits_le32(&mtk_gpt->gpt6_con, GPT_CON_EN); + setbits_le32(&mtk_gpt->gpt6_con, GPT_CON_CLR); /* Set clock source to system clock and set clock divider to 1 */ - write32(&mtk_gpt->gpt4_clk, GPT_SYS_CLK | GPT_CLK_DIV1); - /* Set operation mode to FREERUN mode and enable GTP4 */ - write32(&mtk_gpt->gpt4_con, GPT_CON_EN | GPT_MODE_FREERUN); + write32(&mtk_gpt->gpt6_clk, GPT_SYS_CLK | GPT_CLK_DIV1); + /* Set operation mode to FREERUN mode and enable timer */ + write32(&mtk_gpt->gpt6_con, GPT_CON_EN | GPT_MODE_FREERUN); } diff --git a/src/soc/mediatek/mt8173/timer.c b/src/soc/mediatek/mt8173/timer.c index 2c9995ac05..eb2a1424b2 100644 --- a/src/soc/mediatek/mt8173/timer.c +++ b/src/soc/mediatek/mt8173/timer.c @@ -31,5 +31,5 @@ void timer_prepare(void) */ write32(&mt8173_mcucfg->xgpt_idx, 0); /* Set clock mode to 13Mhz and enable XGPT */ - write32(&mt8173_mcucfg->xgpt_ctl, (0x1 | ((26 / GPT4_MHZ) << 8))); + write32(&mt8173_mcucfg->xgpt_ctl, (0x1 | ((26 / GPT_MHZ) << 8))); }