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-rw-r--r--src/soc/samsung/exynos5250/clock.c677
1 files changed, 677 insertions, 0 deletions
diff --git a/src/soc/samsung/exynos5250/clock.c b/src/soc/samsung/exynos5250/clock.c
new file mode 100644
index 0000000000..8a731be2a3
--- /dev/null
+++ b/src/soc/samsung/exynos5250/clock.c
@@ -0,0 +1,677 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2010 Samsung Electronics
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <assert.h>
+#include <stdlib.h>
+#include <arch/io.h>
+#include <console/console.h>
+#include "clk.h"
+#include "periph.h"
+#include "timer.h"
+
+/* input clock of PLL: SMDK5250 has 24MHz input clock */
+#define CONFIG_SYS_CLK_FREQ 24000000
+
+static struct arm_clk_ratios arm_clk_ratios[] = {
+ {
+ .arm_freq_mhz = 600,
+
+ .apll_mdiv = 0xc8,
+ .apll_pdiv = 0x4,
+ .apll_sdiv = 0x1,
+
+ .arm2_ratio = 0x0,
+ .apll_ratio = 0x1,
+ .pclk_dbg_ratio = 0x1,
+ .atb_ratio = 0x2,
+ .periph_ratio = 0x7,
+ .acp_ratio = 0x7,
+ .cpud_ratio = 0x1,
+ .arm_ratio = 0x0,
+ }, {
+ .arm_freq_mhz = 800,
+
+ .apll_mdiv = 0x64,
+ .apll_pdiv = 0x3,
+ .apll_sdiv = 0x0,
+
+ .arm2_ratio = 0x0,
+ .apll_ratio = 0x1,
+ .pclk_dbg_ratio = 0x1,
+ .atb_ratio = 0x3,
+ .periph_ratio = 0x7,
+ .acp_ratio = 0x7,
+ .cpud_ratio = 0x2,
+ .arm_ratio = 0x0,
+ }, {
+ .arm_freq_mhz = 1000,
+
+ .apll_mdiv = 0x7d,
+ .apll_pdiv = 0x3,
+ .apll_sdiv = 0x0,
+
+ .arm2_ratio = 0x0,
+ .apll_ratio = 0x1,
+ .pclk_dbg_ratio = 0x1,
+ .atb_ratio = 0x4,
+ .periph_ratio = 0x7,
+ .acp_ratio = 0x7,
+ .cpud_ratio = 0x2,
+ .arm_ratio = 0x0,
+ }, {
+ .arm_freq_mhz = 1200,
+
+ .apll_mdiv = 0x96,
+ .apll_pdiv = 0x3,
+ .apll_sdiv = 0x0,
+
+ .arm2_ratio = 0x0,
+ .apll_ratio = 0x3,
+ .pclk_dbg_ratio = 0x1,
+ .atb_ratio = 0x5,
+ .periph_ratio = 0x7,
+ .acp_ratio = 0x7,
+ .cpud_ratio = 0x3,
+ .arm_ratio = 0x0,
+ }, {
+ .arm_freq_mhz = 1400,
+
+ .apll_mdiv = 0xaf,
+ .apll_pdiv = 0x3,
+ .apll_sdiv = 0x0,
+
+ .arm2_ratio = 0x0,
+ .apll_ratio = 0x3,
+ .pclk_dbg_ratio = 0x1,
+ .atb_ratio = 0x6,
+ .periph_ratio = 0x7,
+ .acp_ratio = 0x7,
+ .cpud_ratio = 0x3,
+ .arm_ratio = 0x0,
+ }, {
+ .arm_freq_mhz = 1700,
+
+ .apll_mdiv = 0x1a9,
+ .apll_pdiv = 0x6,
+ .apll_sdiv = 0x0,
+
+ .arm2_ratio = 0x0,
+ .apll_ratio = 0x3,
+ .pclk_dbg_ratio = 0x1,
+ .atb_ratio = 0x6,
+ .periph_ratio = 0x7,
+ .acp_ratio = 0x7,
+ .cpud_ratio = 0x3,
+ .arm_ratio = 0x0,
+ }
+};
+
+/* src_bit div_bit prediv_bit */
+static struct clk_bit_info clk_bit_info[PERIPH_ID_COUNT] = {
+ {0, 4, 0, -1},
+ {4, 4, 4, -1},
+ {8, 4, 8, -1},
+ {12, 4, 12, -1},
+ {0, 4, 0, 8},
+ {4, 4, 16, 24},
+ {8, 4, 0, 8},
+ {12, 4, 16, 24},
+ {-1, -1, -1, -1},
+ {16, 4, 0, 8}, /* PERIPH_ID_SROMC */
+ {20, 4, 16, 24},
+ {24, 4, 0, 8},
+ {0, 4, 0, 4},
+ {4, 4, 12, 16},
+ {-1, 4, -1, -1},
+ {-1, 4, -1, -1},
+ {-1, 4, 24, 0},
+ {-1, 4, 24, 0},
+ {-1, 4, 24, 0},
+ {-1, 4, 24, 0},
+ {-1, 4, 24, 0},
+ {-1, 4, 24, 0},
+ {-1, 4, 24, 0},
+ {-1, 4, 24, 0},
+ {24, 4, 0, -1},
+ {24, 4, 0, -1},
+ {24, 4, 0, -1},
+ {24, 4, 0, -1},
+ {24, 4, 0, -1},
+ {-1, -1, -1, -1},
+ {-1, -1, -1, -1},
+ {-1, -1, -1, -1}, /* PERIPH_ID_I2S1 */
+ {24, 1, 20, -1}, /* PERIPH_ID_SATA */
+};
+
+/* Epll Clock division values to achieve different frequency output */
+static struct st_epll_con_val epll_div[] = {
+ { 192000000, 0, 48, 3, 1, 0 },
+ { 180000000, 0, 45, 3, 1, 0 },
+ { 73728000, 1, 73, 3, 3, 47710 },
+ { 67737600, 1, 90, 4, 3, 20762 },
+ { 49152000, 0, 49, 3, 3, 9961 },
+ { 45158400, 0, 45, 3, 3, 10381 },
+ { 180633600, 0, 45, 3, 1, 10381 }
+};
+
+/* exynos5: return pll clock frequency */
+unsigned long get_pll_clk(int pllreg)
+{
+ unsigned long r, m, p, s, k = 0, mask, fout;
+ unsigned int freq;
+
+ switch (pllreg) {
+ case APLL:
+ r = readl(&exynos_clock->apll_con0);
+ break;
+ case BPLL:
+ r = readl(&exynos_clock->bpll_con0);
+ break;
+ case MPLL:
+ r = readl(&exynos_clock->mpll_con0);
+ break;
+ case EPLL:
+ r = readl(&exynos_clock->epll_con0);
+ k = readl(&exynos_clock->epll_con1);
+ break;
+ case VPLL:
+ r = readl(&exynos_clock->vpll_con0);
+ k = readl(&exynos_clock->vpll_con1);
+ break;
+ default:
+ printk(BIOS_DEBUG, "Unsupported PLL (%d)\n", pllreg);
+ return 0;
+ }
+
+ /*
+ * APLL_CON: MIDV [25:16]
+ * MPLL_CON: MIDV [25:16]
+ * EPLL_CON: MIDV [24:16]
+ * VPLL_CON: MIDV [24:16]
+ */
+ if (pllreg == APLL || pllreg == BPLL || pllreg == MPLL)
+ mask = 0x3ff;
+ else
+ mask = 0x1ff;
+
+ m = (r >> 16) & mask;
+
+ /* PDIV [13:8] */
+ p = (r >> 8) & 0x3f;
+ /* SDIV [2:0] */
+ s = r & 0x7;
+
+ freq = CONFIG_SYS_CLK_FREQ;
+
+ if (pllreg == EPLL) {
+ k = k & 0xffff;
+ /* FOUT = (MDIV + K / 65536) * FIN / (PDIV * 2^SDIV) */
+ fout = (m + k / 65536) * (freq / (p * (1 << s)));
+ } else if (pllreg == VPLL) {
+ k = k & 0xfff;
+ /* FOUT = (MDIV + K / 1024) * FIN / (PDIV * 2^SDIV) */
+ fout = (m + k / 1024) * (freq / (p * (1 << s)));
+ } else {
+ /* FOUT = MDIV * FIN / (PDIV * 2^SDIV) */
+ fout = m * (freq / (p * (1 << s)));
+ }
+
+ return fout;
+}
+
+unsigned long clock_get_periph_rate(enum periph_id peripheral)
+{
+ struct clk_bit_info *bit_info = &clk_bit_info[peripheral];
+ unsigned long sclk, sub_clk;
+ unsigned int src, div, sub_div;
+
+ switch (peripheral) {
+ case PERIPH_ID_UART0:
+ case PERIPH_ID_UART1:
+ case PERIPH_ID_UART2:
+ case PERIPH_ID_UART3:
+ src = readl(&exynos_clock->src_peric0);
+ div = readl(&exynos_clock->div_peric0);
+ break;
+ case PERIPH_ID_PWM0:
+ case PERIPH_ID_PWM1:
+ case PERIPH_ID_PWM2:
+ case PERIPH_ID_PWM3:
+ case PERIPH_ID_PWM4:
+ src = readl(&exynos_clock->src_peric0);
+ div = readl(&exynos_clock->div_peric3);
+ break;
+ case PERIPH_ID_SPI0:
+ case PERIPH_ID_SPI1:
+ src = readl(&exynos_clock->src_peric1);
+ div = readl(&exynos_clock->div_peric1);
+ break;
+ case PERIPH_ID_SPI2:
+ src = readl(&exynos_clock->src_peric1);
+ div = readl(&exynos_clock->div_peric2);
+ break;
+ case PERIPH_ID_SPI3:
+ case PERIPH_ID_SPI4:
+ src = readl(&exynos_clock->sclk_src_isp);
+ div = readl(&exynos_clock->sclk_div_isp);
+ break;
+ case PERIPH_ID_SATA:
+ src = readl(&exynos_clock->src_fsys);
+ div = readl(&exynos_clock->div_fsys0);
+ break;
+ case PERIPH_ID_SDMMC0:
+ case PERIPH_ID_SDMMC1:
+ case PERIPH_ID_SDMMC2:
+ case PERIPH_ID_SDMMC3:
+ src = readl(&exynos_clock->src_fsys);
+ div = readl(&exynos_clock->div_fsys1);
+ break;
+ case PERIPH_ID_I2C0:
+ case PERIPH_ID_I2C1:
+ case PERIPH_ID_I2C2:
+ case PERIPH_ID_I2C3:
+ case PERIPH_ID_I2C4:
+ case PERIPH_ID_I2C5:
+ case PERIPH_ID_I2C6:
+ case PERIPH_ID_I2C7:
+ sclk = get_pll_clk(MPLL);
+ sub_div = ((readl(&exynos_clock->div_top1)
+ >> bit_info->div_bit) & 0x7) + 1;
+ div = ((readl(&exynos_clock->div_top0)
+ >> bit_info->prediv_bit) & 0x7) + 1;
+ return (sclk / sub_div) / div;
+ default:
+ printk(BIOS_DEBUG, "%s: invalid peripheral %d", __func__, peripheral);
+ return -1;
+ };
+
+ src = (src >> bit_info->src_bit) & ((1 << bit_info->n_src_bits) - 1);
+ if (peripheral == PERIPH_ID_SATA) {
+ if (src)
+ sclk = get_pll_clk(BPLL);
+ else
+ sclk = get_pll_clk(MPLL);
+ } else {
+ if (src == SRC_MPLL)
+ sclk = get_pll_clk(MPLL);
+ else if (src == SRC_EPLL)
+ sclk = get_pll_clk(EPLL);
+ else if (src == SRC_VPLL)
+ sclk = get_pll_clk(VPLL);
+ else
+ return 0;
+ }
+
+ sub_div = (div >> bit_info->div_bit) & 0xf;
+ sub_clk = sclk / (sub_div + 1);
+
+ if (peripheral == PERIPH_ID_SDMMC0 || peripheral == PERIPH_ID_SDMMC2) {
+ div = (div >> bit_info->prediv_bit) & 0xff;
+ return sub_clk / (div + 1);
+ }
+
+ return sub_clk;
+}
+
+/* exynos5: return ARM clock frequency */
+unsigned long get_arm_clk(void)
+{
+ unsigned long div;
+ unsigned long armclk;
+ unsigned int arm_ratio;
+ unsigned int arm2_ratio;
+
+ div = readl(&exynos_clock->div_cpu0);
+
+ /* ARM_RATIO: [2:0], ARM2_RATIO: [30:28] */
+ arm_ratio = (div >> 0) & 0x7;
+ arm2_ratio = (div >> 28) & 0x7;
+
+ armclk = get_pll_clk(APLL) / (arm_ratio + 1);
+ armclk /= (arm2_ratio + 1);
+
+ return armclk;
+}
+
+struct arm_clk_ratios *get_arm_clk_ratios(void)
+{
+ struct arm_clk_ratios *arm_ratio;
+ unsigned long arm_freq = 1700; /* FIXME: use get_arm_clk() */
+ int i;
+
+ for (i = 0, arm_ratio = arm_clk_ratios; i < ARRAY_SIZE(arm_clk_ratios);
+ i++, arm_ratio++) {
+ if (arm_ratio->arm_freq_mhz == arm_freq)
+ return arm_ratio;
+ }
+
+ return NULL;
+}
+
+/* exynos5: set the mmc clock */
+void set_mmc_clk(int dev_index, unsigned int div)
+{
+ unsigned int *addr;
+ unsigned int val;
+
+ /*
+ * CLK_DIV_FSYS1
+ * MMC0_PRE_RATIO [15:8], MMC1_PRE_RATIO [31:24]
+ * CLK_DIV_FSYS2
+ * MMC2_PRE_RATIO [15:8], MMC3_PRE_RATIO [31:24]
+ */
+ if (dev_index < 2) {
+ addr = &exynos_clock->div_fsys1;
+ } else {
+ addr = &exynos_clock->div_fsys2;
+ dev_index -= 2;
+ }
+
+ val = readl(addr);
+ val &= ~(0xff << ((dev_index << 4) + 8));
+ val |= (div & 0xff) << ((dev_index << 4) + 8);
+ writel(val, addr);
+}
+
+void clock_ll_set_pre_ratio(enum periph_id periph_id, unsigned divisor)
+{
+ unsigned shift;
+ unsigned mask = 0xff;
+ u32 *reg;
+
+ /*
+ * For now we only handle a very small subset of peripherals here.
+ * Others will need to (and do) mangle the clock registers
+ * themselves, At some point it is hoped that this function can work
+ * from a table or calculated register offset / mask. For now this
+ * is at least better than spreading clock control code around
+ * U-Boot.
+ */
+ switch (periph_id) {
+ case PERIPH_ID_SPI0:
+ reg = &exynos_clock->div_peric1;
+ shift = 8;
+ break;
+ case PERIPH_ID_SPI1:
+ reg = &exynos_clock->div_peric1;
+ shift = 24;
+ break;
+ case PERIPH_ID_SPI2:
+ reg = &exynos_clock->div_peric2;
+ shift = 8;
+ break;
+ case PERIPH_ID_SPI3:
+ reg = &exynos_clock->sclk_div_isp;
+ shift = 4;
+ break;
+ case PERIPH_ID_SPI4:
+ reg = &exynos_clock->sclk_div_isp;
+ shift = 16;
+ break;
+ default:
+ printk(BIOS_DEBUG, "%s: Unsupported peripheral ID %d\n", __func__,
+ periph_id);
+ return;
+ }
+ clrsetbits_le32(reg, mask << shift, (divisor & mask) << shift);
+}
+
+void clock_ll_set_ratio(enum periph_id periph_id, unsigned divisor)
+{
+ unsigned shift;
+ unsigned mask = 0xff;
+ u32 *reg;
+
+ switch (periph_id) {
+ case PERIPH_ID_SPI0:
+ reg = &exynos_clock->div_peric1;
+ shift = 0;
+ break;
+ case PERIPH_ID_SPI1:
+ reg = &exynos_clock->div_peric1;
+ shift = 16;
+ break;
+ case PERIPH_ID_SPI2:
+ reg = &exynos_clock->div_peric2;
+ shift = 0;
+ break;
+ case PERIPH_ID_SPI3:
+ reg = &exynos_clock->sclk_div_isp;
+ shift = 0;
+ break;
+ case PERIPH_ID_SPI4:
+ reg = &exynos_clock->sclk_div_isp;
+ shift = 12;
+ break;
+ default:
+ printk(BIOS_DEBUG, "%s: Unsupported peripheral ID %d\n", __func__,
+ periph_id);
+ return;
+ }
+ clrsetbits_le32(reg, mask << shift, (divisor & mask) << shift);
+}
+
+/**
+ * Linearly searches for the most accurate main and fine stage clock scalars
+ * (divisors) for a specified target frequency and scalar bit sizes by checking
+ * all multiples of main_scalar_bits values. Will always return scalars up to or
+ * slower than target.
+ *
+ * @param main_scalar_bits Number of main scalar bits, must be > 0 and < 32
+ * @param fine_scalar_bits Number of fine scalar bits, must be > 0 and < 32
+ * @param input_freq Clock frequency to be scaled in Hz
+ * @param target_freq Desired clock frequency in Hz
+ * @param best_fine_scalar Pointer to store the fine stage divisor
+ *
+ * @return best_main_scalar Main scalar for desired frequency or -1 if none
+ * found
+ */
+static int clock_calc_best_scalar(unsigned int main_scaler_bits,
+ unsigned int fine_scalar_bits, unsigned int input_rate,
+ unsigned int target_rate, unsigned int *best_fine_scalar)
+{
+ int i;
+ int best_main_scalar = -1;
+ unsigned int best_error = target_rate;
+ const unsigned int cap = (1 << fine_scalar_bits) - 1;
+ const unsigned int loops = 1 << main_scaler_bits;
+
+ printk(BIOS_DEBUG, "Input Rate is %u, Target is %u, Cap is %u\n", input_rate,
+ target_rate, cap);
+
+ ASSERT(best_fine_scalar != NULL);
+ ASSERT(main_scaler_bits <= fine_scalar_bits);
+
+ *best_fine_scalar = 1;
+
+ if (input_rate == 0 || target_rate == 0)
+ return -1;
+
+ if (target_rate >= input_rate)
+ return 1;
+
+ for (i = 1; i <= loops; i++) {
+ const unsigned int effective_div = MAX(MIN(input_rate / i /
+ target_rate, cap), 1);
+ const unsigned int effective_rate = input_rate / i /
+ effective_div;
+ const int error = target_rate - effective_rate;
+
+ printk(BIOS_DEBUG, "%d|effdiv:%u, effrate:%u, error:%d\n", i, effective_div,
+ effective_rate, error);
+
+ if (error >= 0 && error <= best_error) {
+ best_error = error;
+ best_main_scalar = i;
+ *best_fine_scalar = effective_div;
+ }
+ }
+
+ return best_main_scalar;
+}
+
+int clock_set_rate(enum periph_id periph_id, unsigned int rate)
+{
+ int main_scalar;
+ unsigned int fine;
+
+ switch (periph_id) {
+ case PERIPH_ID_SPI0:
+ case PERIPH_ID_SPI1:
+ case PERIPH_ID_SPI2:
+ case PERIPH_ID_SPI3:
+ case PERIPH_ID_SPI4:
+ main_scalar = clock_calc_best_scalar(4, 8, 400000000, rate, &fine);
+ if (main_scalar < 0) {
+ printk(BIOS_DEBUG, "%s: Cannot set clock rate for periph %d",
+ __func__, periph_id);
+ return -1;
+ }
+ clock_ll_set_ratio(periph_id, main_scalar - 1);
+ clock_ll_set_pre_ratio(periph_id, fine - 1);
+ break;
+ default:
+ printk(BIOS_DEBUG, "%s: Unsupported peripheral ID %d\n", __func__,
+ periph_id);
+ return -1;
+ }
+
+ return 0;
+}
+
+int clock_set_mshci(enum periph_id peripheral)
+{
+ u32 *addr;
+ unsigned int clock;
+ unsigned int tmp;
+ unsigned int i;
+
+ /* get mpll clock */
+ clock = get_pll_clk(MPLL) / 1000000;
+
+ /*
+ * CLK_DIV_FSYS1
+ * MMC0_PRE_RATIO [15:8], MMC0_RATIO [3:0]
+ * CLK_DIV_FSYS2
+ * MMC2_PRE_RATIO [15:8], MMC2_RATIO [3:0]
+ */
+ switch (peripheral) {
+ case PERIPH_ID_SDMMC0:
+ addr = &exynos_clock->div_fsys1;
+ break;
+ case PERIPH_ID_SDMMC2:
+ addr = &exynos_clock->div_fsys2;
+ break;
+ default:
+ printk(BIOS_DEBUG, "invalid peripheral\n");
+ return -1;
+ }
+ tmp = readl(addr) & ~0xff0f;
+ for (i = 0; i <= 0xf; i++) {
+ if ((clock / (i + 1)) <= 400) {
+ writel(tmp | i << 0, addr);
+ break;
+ }
+ }
+ return 0;
+}
+
+int clock_epll_set_rate(unsigned long rate)
+{
+ unsigned int epll_con, epll_con_k;
+ unsigned int i;
+ unsigned int lockcnt;
+ struct mono_time current, end;
+
+ epll_con = readl(&exynos_clock->epll_con0);
+ epll_con &= ~((EPLL_CON0_LOCK_DET_EN_MASK <<
+ EPLL_CON0_LOCK_DET_EN_SHIFT) |
+ EPLL_CON0_MDIV_MASK << EPLL_CON0_MDIV_SHIFT |
+ EPLL_CON0_PDIV_MASK << EPLL_CON0_PDIV_SHIFT |
+ EPLL_CON0_SDIV_MASK << EPLL_CON0_SDIV_SHIFT);
+
+ for (i = 0; i < ARRAY_SIZE(epll_div); i++) {
+ if (epll_div[i].freq_out == rate)
+ break;
+ }
+
+ if (i == ARRAY_SIZE(epll_div))
+ return -1;
+
+ epll_con_k = epll_div[i].k_dsm << 0;
+ epll_con |= epll_div[i].en_lock_det << EPLL_CON0_LOCK_DET_EN_SHIFT;
+ epll_con |= epll_div[i].m_div << EPLL_CON0_MDIV_SHIFT;
+ epll_con |= epll_div[i].p_div << EPLL_CON0_PDIV_SHIFT;
+ epll_con |= epll_div[i].s_div << EPLL_CON0_SDIV_SHIFT;
+
+ /*
+ * Required period ( in cycles) to generate a stable clock output.
+ * The maximum clock time can be up to 3000 * PDIV cycles of PLLs
+ * frequency input (as per spec)
+ */
+ lockcnt = 3000 * epll_div[i].p_div;
+
+ writel(lockcnt, &exynos_clock->epll_lock);
+ writel(epll_con, &exynos_clock->epll_con0);
+ writel(epll_con_k, &exynos_clock->epll_con1);
+
+ timer_monotonic_get(&current);
+ end = current;
+ mono_time_add_msecs(&end, TIMEOUT_EPLL_LOCK);
+
+ while (!(readl(&exynos_clock->epll_con0) &
+ (0x1 << EXYNOS5_EPLLCON0_LOCKED_SHIFT))) {
+ if (mono_time_after(&current, &end)) {
+ printk(BIOS_DEBUG,
+ "%s: Timeout waiting for EPLL lock\n",
+ __func__);
+ return -1;
+ }
+ timer_monotonic_get(&current);
+ }
+
+ return 0;
+}
+
+void clock_select_i2s_clk_source(void)
+{
+ clrsetbits_le32(&exynos_clock->src_peric1, AUDIO1_SEL_MASK,
+ (CLK_SRC_SCLK_EPLL));
+}
+
+int clock_set_i2s_clk_prescaler(unsigned int src_frq, unsigned int dst_frq)
+{
+ unsigned int div ;
+
+ if ((dst_frq == 0) || (src_frq == 0)) {
+ printk(BIOS_DEBUG, "%s: Invalid frequency input for prescaler\n", __func__);
+ printk(BIOS_DEBUG, "src frq = %d des frq = %d ", src_frq, dst_frq);
+ return -1;
+ }
+
+ div = (src_frq / dst_frq);
+ if (div > AUDIO_1_RATIO_MASK) {
+ printk(BIOS_DEBUG, "%s: Frequency ratio is out of range\n", __func__);
+ printk(BIOS_DEBUG, "src frq = %d des frq = %d ", src_frq, dst_frq);
+ return -1;
+ }
+ clrsetbits_le32(&exynos_clock->div_peric4, AUDIO_1_RATIO_MASK,
+ (div & AUDIO_1_RATIO_MASK));
+ return 0;
+}