From bed1b602d0cb6027c1b796cb1e44f335e56e0471 Mon Sep 17 00:00:00 2001 From: Lean Sheng Tan Date: Wed, 16 Jun 2021 09:41:37 -0700 Subject: soc/intel/common: Refine pmc_get_xtal_freq function 1. Remove 'PCH_EPOC_XTAL_FREQ(__epoc)' macro since it only be used in 1 place. 2. Transform macro into more readable C code. 3. Add additional case check to make sure the returned value is defined in the 'pch_pmc_xtal' enum. Signed-off-by: Lean Sheng Tan Change-Id: If57a99bf8e837a6eb8f225297399b1f5363cfa85 Reviewed-on: https://review.coreboot.org/c/coreboot/+/55587 Tested-by: build bot (Jenkins) Reviewed-by: Angel Pons --- .../intel/common/block/include/intelblocks/pmclib.h | 4 ++-- src/soc/intel/common/block/pmc/pmclib.c | 21 ++++++++++++++++++--- 2 files changed, 20 insertions(+), 5 deletions(-) (limited to 'src/soc/intel/common/block') diff --git a/src/soc/intel/common/block/include/intelblocks/pmclib.h b/src/soc/intel/common/block/include/intelblocks/pmclib.h index a54ae18a8c..4972a09f8b 100644 --- a/src/soc/intel/common/block/include/intelblocks/pmclib.h +++ b/src/soc/intel/common/block/include/intelblocks/pmclib.h @@ -7,19 +7,19 @@ #include #define PCH_PMC_EPOC 0x18EC -/* XTAL frequency in bits 21, 20, 17 */ -#define PCH_EPOC_XTAL_FREQ(__epoc) ((((__epoc) >> 19) & 0x6) | ((__epoc) >> 17 & 0x1)) /** * enum pch_pmc_xtal - External crystal oscillator frequency. * @XTAL_24_MHZ: 24 MHz external crystal. * @XTAL_19_2_MHZ: 19.2 MHz external crystal. * @XTAL_38_4_MHZ: 38.4 MHz external crystal. + * @XTAL_UNKNOWN_FREQ: Unsupported external crystal. */ enum pch_pmc_xtal { XTAL_24_MHZ, XTAL_19_2_MHZ, XTAL_38_4_MHZ, + XTAL_UNKNOWN_FREQ = 0xf, }; /* diff --git a/src/soc/intel/common/block/pmc/pmclib.c b/src/soc/intel/common/block/pmc/pmclib.c index 64c25ff5fe..81d25e02a0 100644 --- a/src/soc/intel/common/block/pmc/pmclib.c +++ b/src/soc/intel/common/block/pmc/pmclib.c @@ -732,7 +732,22 @@ enum pch_pmc_xtal pmc_get_xtal_freq(void) if (!CONFIG(PMC_EPOC)) dead_code(); - const uintptr_t pmcbase = soc_read_pmc_base(); - - return PCH_EPOC_XTAL_FREQ(read32((uint32_t *)(pmcbase + PCH_PMC_EPOC))); + uint32_t xtal_freq = 0; + const uint32_t epoc = read32p(soc_read_pmc_base() + PCH_PMC_EPOC); + + /* XTAL frequency in bits 21, 20, 17 */ + xtal_freq |= !!(epoc & (1 << 21)) << 2; + xtal_freq |= !!(epoc & (1 << 20)) << 1; + xtal_freq |= !!(epoc & (1 << 17)) << 0; + switch (xtal_freq) { + case 0: + return XTAL_24_MHZ; + case 1: + return XTAL_19_2_MHZ; + case 2: + return XTAL_38_4_MHZ; + default: + printk(BIOS_ERR, "Unknown EPOC XTAL frequency setting %u\n", xtal_freq); + return XTAL_UNKNOWN_FREQ; + } } -- cgit v1.2.3