X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=qemu%2Froms%2Fu-boot%2Farch%2Farm%2Fcpu%2Farm920t%2Fep93xx%2Fspeed.c;fp=qemu%2Froms%2Fu-boot%2Farch%2Farm%2Fcpu%2Farm920t%2Fep93xx%2Fspeed.c;h=9dc60b6ff27627e7bbf6799675dada6b1a2d158c;hb=e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb;hp=0000000000000000000000000000000000000000;hpb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;p=kvmfornfv.git diff --git a/qemu/roms/u-boot/arch/arm/cpu/arm920t/ep93xx/speed.c b/qemu/roms/u-boot/arch/arm/cpu/arm920t/ep93xx/speed.c new file mode 100644 index 000000000..9dc60b6ff --- /dev/null +++ b/qemu/roms/u-boot/arch/arm/cpu/arm920t/ep93xx/speed.c @@ -0,0 +1,96 @@ +/* + * Cirrus Logic EP93xx PLL support. + * + * Copyright (C) 2009 Matthias Kaehlcke + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include +#include +#include + +/* + * CONFIG_SYS_CLK_FREQ should be defined as the input frequency of the PLL. + * + * get_FCLK(), get_HCLK(), get_PCLK() and get_UCLK() return the clock of + * the specified bus in HZ. + */ + +/* + * return the PLL output frequency + * + * PLL rate = CONFIG_SYS_CLK_FREQ * (X1FBD + 1) * (X2FBD + 1) + * / (X2IPD + 1) / 2^PS + */ +static ulong get_PLLCLK(uint32_t *pllreg) +{ + uint8_t i; + const uint32_t clkset = readl(pllreg); + uint64_t rate = CONFIG_SYS_CLK_FREQ; + rate *= ((clkset >> SYSCON_CLKSET_PLL_X1FBD1_SHIFT) & 0x1f) + 1; + rate *= ((clkset >> SYSCON_CLKSET_PLL_X2FBD2_SHIFT) & 0x3f) + 1; + do_div(rate, (clkset & 0x1f) + 1); /* X2IPD */ + for (i = 0; i < ((clkset >> SYSCON_CLKSET_PLL_PS_SHIFT) & 3); i++) + rate >>= 1; + + return (ulong)rate; +} + +/* return FCLK frequency */ +ulong get_FCLK() +{ + const uint8_t fclk_divisors[] = { 1, 2, 4, 8, 16, 1, 1, 1 }; + struct syscon_regs *syscon = (struct syscon_regs *)SYSCON_BASE; + + const uint32_t clkset1 = readl(&syscon->clkset1); + const uint8_t fclk_div = + fclk_divisors[(clkset1 >> SYSCON_CLKSET1_FCLK_DIV_SHIFT) & 7]; + const ulong fclk_rate = get_PLLCLK(&syscon->clkset1) / fclk_div; + + return fclk_rate; +} + +/* return HCLK frequency */ +ulong get_HCLK(void) +{ + const uint8_t hclk_divisors[] = { 1, 2, 4, 5, 6, 8, 16, 32 }; + struct syscon_regs *syscon = (struct syscon_regs *)SYSCON_BASE; + + const uint32_t clkset1 = readl(&syscon->clkset1); + const uint8_t hclk_div = + hclk_divisors[(clkset1 >> SYSCON_CLKSET1_HCLK_DIV_SHIFT) & 7]; + const ulong hclk_rate = get_PLLCLK(&syscon->clkset1) / hclk_div; + + return hclk_rate; +} + +/* return PCLK frequency */ +ulong get_PCLK(void) +{ + const uint8_t pclk_divisors[] = { 1, 2, 4, 8 }; + struct syscon_regs *syscon = (struct syscon_regs *)SYSCON_BASE; + + const uint32_t clkset1 = readl(&syscon->clkset1); + const uint8_t pclk_div = + pclk_divisors[(clkset1 >> SYSCON_CLKSET1_PCLK_DIV_SHIFT) & 3]; + const ulong pclk_rate = get_HCLK() / pclk_div; + + return pclk_rate; +} + +/* return UCLK frequency */ +ulong get_UCLK(void) +{ + struct syscon_regs *syscon = (struct syscon_regs *)SYSCON_BASE; + ulong uclk_rate; + + const uint32_t value = readl(&syscon->pwrcnt); + if (value & SYSCON_PWRCNT_UART_BAUD) + uclk_rate = CONFIG_SYS_CLK_FREQ; + else + uclk_rate = CONFIG_SYS_CLK_FREQ / 2; + + return uclk_rate; +}