From 38779e6b8304cf4078bede5512ca07f609f3ea63 Mon Sep 17 00:00:00 2001 From: Weiyi Lu Date: Wed, 6 May 2020 11:05:15 +0800 Subject: soc/mediatek: improve ca53 frequency change procedure To change frequency, the SOC PLL team suggests procedure below: First, we need to enable the intermediate clock and switch the ca53 clock source to the intermediate clock. Second, disable the armpll_ll clock output. Third, raise armpll_ll frequency and enable the clock output. The last, switch the ca53 clock source back to armpll_ll and disable the intermediate clock. BUG=b:154451241 BRANCH=jacuzzi TEST=Boots correctly on Jacuzzi. Signed-off-by: Weiyi Lu Change-Id: Ib9556ba340da272fb62588f45851c93373cfa919 Reviewed-on: https://review.coreboot.org/c/coreboot/+/41077 Reviewed-by: Hung-Te Lin Tested-by: build bot (Jenkins) --- src/soc/mediatek/mt8183/include/soc/pll.h | 1 + src/soc/mediatek/mt8183/pll.c | 22 ++++++++++++++++++++++ 2 files changed, 23 insertions(+) (limited to 'src') diff --git a/src/soc/mediatek/mt8183/include/soc/pll.h b/src/soc/mediatek/mt8183/include/soc/pll.h index 3fa7366942..3aa77c9f3b 100644 --- a/src/soc/mediatek/mt8183/include/soc/pll.h +++ b/src/soc/mediatek/mt8183/include/soc/pll.h @@ -217,6 +217,7 @@ enum { MUX_MASK = 0x3 << 9, MUX_SRC_ARMPLL = 0x1 << 9, + MUX_SRC_DIV_PLL1 = 0x2 << 9, }; enum { diff --git a/src/soc/mediatek/mt8183/pll.c b/src/soc/mediatek/mt8183/pll.c index 39dfa264e3..dedd59d4f2 100644 --- a/src/soc/mediatek/mt8183/pll.c +++ b/src/soc/mediatek/mt8183/pll.c @@ -365,5 +365,27 @@ void mt_pll_init(void) void mt_pll_raise_ca53_freq(u32 freq) { + /* enable [4] intermediate clock armpll_divider_pll1_ck */ + setbits32(&mtk_topckgen->clk_misc_cfg_0, 1 << 4); + + /* switch ca53 clock source to intermediate clock */ + clrsetbits32(&mt8183_mcucfg->mp0_pll_divider_cfg, MUX_MASK, + MUX_SRC_DIV_PLL1); + + /* disable armpll_ll frequency output */ + clrbits32(plls[APMIXED_ARMPLL_LL].reg, PLL_EN); + + /* raise armpll_ll frequency */ pll_set_rate(&plls[APMIXED_ARMPLL_LL], freq); + + /* enable armpll_ll frequency output */ + setbits32(plls[APMIXED_ARMPLL_LL].reg, PLL_EN); + udelay(PLL_EN_DELAY); + + /* switch ca53 clock source back to armpll_ll */ + clrsetbits32(&mt8183_mcucfg->mp0_pll_divider_cfg, MUX_MASK, + MUX_SRC_ARMPLL); + + /* disable [4] intermediate clock armpll_divider_pll1_ck */ + clrbits32(&mtk_topckgen->clk_misc_cfg_0, 1 << 4); } -- cgit v1.2.3