aboutsummaryrefslogtreecommitdiff
path: root/src/soc/samsung/exynos5420/clock.c
diff options
context:
space:
mode:
authorHung-Te Lin <hungte@chromium.org>2013-09-27 12:45:45 +0800
committerIsaac Christensen <isaac.christensen@se-eng.com>2014-08-26 17:55:18 +0200
commit22d0ca0ceb802675cdcab1472b8477066f729373 (patch)
tree79e2e38a2c6b34125f48b05cfd7f9ef3c88c833d /src/soc/samsung/exynos5420/clock.c
parentb123e0d3345554d7e93361bb4511a53bc95d41a1 (diff)
armv7: Move Exynos from 'cpu' to 'soc'.
The Exynos family and most ARM products are SoC, not just CPU. We used to put ARM code in src/cpu to avoid polluting the code base for what was essentially an experiment at the time. Now that it's past the experimental phase and we're going to see more SoCs (including intel/baytrail) in coreboot. Change-Id: I5ea1f822664244edf5f77087bc8018d7c535f81c Reviewed-on: https://chromium-review.googlesource.com/170891 Tested-by: Hung-Te Lin <hungte@chromium.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org> Reviewed-by: Ronald Minnich <rminnich@chromium.org> Commit-Queue: Hung-Te Lin <hungte@chromium.org> (cherry picked from commit c8bb8fe0b20be37465f93c738d80e7e43033670a) Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com> Reviewed-on: http://review.coreboot.org/6739 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/soc/samsung/exynos5420/clock.c')
-rw-r--r--src/soc/samsung/exynos5420/clock.c639
1 files changed, 639 insertions, 0 deletions
diff --git a/src/soc/samsung/exynos5420/clock.c b/src/soc/samsung/exynos5420/clock.c
new file mode 100644
index 0000000000..7043310a43
--- /dev/null
+++ b/src/soc/samsung/exynos5420/clock.c
@@ -0,0 +1,639 @@
+/*
+ * 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 <timer.h>
+#include <arch/io.h>
+#include <console/console.h>
+#include "clk.h"
+#include "periph.h"
+
+/* input clock of PLL: SMDK5420 has 24MHz input clock */
+#define CONFIG_SYS_CLK_FREQ 24000000
+
+/* Epll Clock division values to achive 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 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;
+ case BPLL:
+ r = readl(&exynos_clock->bpll_con0);
+ break;
+ case RPLL:
+ r = readl(&exynos_clock->rpll_con0);
+ k = readl(&exynos_clock->rpll_con1);
+ break;
+ case SPLL:
+ r = readl(&exynos_clock->spll_con0);
+ break;
+ case CPLL:
+ r = readl(&exynos_clock->cpll_con0);
+ break;
+ case DPLL:
+ r = readl(&exynos_clock->dpll_con0);
+ 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 ||
+ pllreg == SPLL)
+ 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 || pllreg == RPLL) {
+ 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;
+}
+
+enum peripheral_clock_select {
+ PERIPH_SRC_CPLL = 1,
+ PERIPH_SRC_DPLL = 2,
+ PERIPH_SRC_MPLL = 3,
+ PERIPH_SRC_SPLL = 4,
+ PERIPH_SRC_IPLL = 5,
+ PERIPH_SRC_EPLL = 6,
+ PERIPH_SRC_RPLL = 7,
+};
+
+static int clock_select_to_pll(enum peripheral_clock_select sel)
+{
+ int pll;
+
+ switch (sel) {
+ case PERIPH_SRC_CPLL:
+ pll = CPLL;
+ break;
+ case PERIPH_SRC_DPLL:
+ pll = DPLL;
+ break;
+ case PERIPH_SRC_MPLL:
+ pll = MPLL;
+ break;
+ case PERIPH_SRC_SPLL:
+ pll = SPLL;
+ break;
+ case PERIPH_SRC_IPLL:
+ pll = IPLL;
+ break;
+ case PERIPH_SRC_EPLL:
+ pll = EPLL;
+ break;
+ case PERIPH_SRC_RPLL:
+ pll = RPLL;
+ break;
+ default:
+ pll = -1;
+ break;
+ }
+
+ return pll;
+}
+
+unsigned long clock_get_periph_rate(enum periph_id peripheral)
+{
+ unsigned long sclk;
+ unsigned int src, div;
+
+ switch (peripheral) {
+ case PERIPH_ID_UART0:
+ src = (readl(&exynos_clock->clk_src_peric0) >> 4) & 0x7;
+ div = (readl(&exynos_clock->clk_div_peric0) >> 8) & 0xf;
+ break;
+ case PERIPH_ID_UART1:
+ src = (readl(&exynos_clock->clk_src_peric0) >> 8) & 0x7;
+ div = (readl(&exynos_clock->clk_div_peric0) >> 12) & 0xf;
+ break;
+ case PERIPH_ID_UART2:
+ src = (readl(&exynos_clock->clk_src_peric0) >> 12) & 0x7;
+ div = (readl(&exynos_clock->clk_div_peric0) >> 16) & 0xf;
+ break;
+ case PERIPH_ID_UART3:
+ src = (readl(&exynos_clock->clk_src_peric0) >> 16) & 0x7;
+ div = (readl(&exynos_clock->clk_div_peric0) >> 20) & 0xf;
+ 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->clk_src_peric0) >> 24) & 0x7;
+ div = (readl(&exynos_clock->clk_div_peric0) >> 28) & 0x7;
+ break;
+ case PERIPH_ID_SPI0:
+ src = (readl(&exynos_clock->clk_src_peric1) >> 20) & 0x7;
+ div = (readl(&exynos_clock->clk_div_peric1) >> 20) & 0xf;
+ break;
+ case PERIPH_ID_SPI1:
+ src = (readl(&exynos_clock->clk_src_peric1) >> 24) & 0x7;
+ div = (readl(&exynos_clock->clk_div_peric1) >> 24) & 0xf;
+ break;
+ case PERIPH_ID_SPI2:
+ src = (readl(&exynos_clock->clk_src_peric1) >> 28) & 0x7;
+ div = (readl(&exynos_clock->clk_div_peric1) >> 28) & 0xf;
+ break;
+ case PERIPH_ID_SPI3: /* aka SPI0_ISP */
+ src = (readl(&exynos_clock->clk_src_isp) >> 16) & 0x7;
+ div = (readl(&exynos_clock->clk_div_isp0) >> 0) & 0x7;
+ break;
+ case PERIPH_ID_SPI4: /* aka SPI1_ISP */
+ src = (readl(&exynos_clock->clk_src_isp) >> 12) & 0x7;
+ div = (readl(&exynos_clock->clk_div_isp1) >> 4) & 0x7;
+ 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:
+ case PERIPH_ID_I2C8:
+ case PERIPH_ID_I2C9:
+ case PERIPH_ID_I2C10:
+ /*
+ * I2C block parent clock selection is different from other
+ * peripherals, so we handle it all here.
+ * TODO: Add a helper function like with the peripheral clock
+ * select fields?
+ */
+ src = (readl(&exynos_clock->clk_src_top1) >> 8) & 0x3;
+ if (src == 0x0)
+ src = CPLL;
+ else if (src == 0x1)
+ src = DPLL;
+ else if (src == 0x2)
+ src = MPLL;
+ else
+ return -1;
+
+ sclk = get_pll_clk(src);
+ div = ((readl(&exynos_clock->clk_div_top1) >> 8) & 0x3f) + 1;
+ return sclk / div;
+ default:
+ printk(BIOS_DEBUG, "%s: invalid peripheral %d",
+ __func__, peripheral);
+ return -1;
+ };
+
+ src = clock_select_to_pll(src);
+ if (src < 0) {
+ printk(BIOS_DEBUG, "%s: cannot determine source PLL", __func__);
+ return -1;
+ }
+
+ sclk = get_pll_clk(src);
+
+ return sclk / (div + 1);
+}
+
+/* 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->clk_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;
+}
+
+/* exynos5: get the mmc clock */
+static unsigned long get_mmc_clk(int dev_index)
+{
+ unsigned long uclk, sclk;
+ unsigned int sel, ratio;
+ int shift = 0;
+
+ sel = readl(&exynos_clock->clk_src_fsys);
+ sel = (sel >> ((dev_index * 4) + 8)) & 0x7;
+
+ if (sel == 0x3)
+ sclk = get_pll_clk(MPLL);
+ else if (sel == 0x6)
+ sclk = get_pll_clk(EPLL);
+ else
+ return 0;
+
+ ratio = readl(&exynos_clock->clk_div_fsys1);
+
+ shift = dev_index * 10;
+
+ ratio = (ratio >> shift) & 0x3ff;
+ uclk = (sclk / (ratio + 1));
+ printk(BIOS_DEBUG, "%s(%d): %lu\n", __func__, dev_index, uclk);
+
+ return uclk;
+}
+
+/* exynos5: set the mmc clock */
+void set_mmc_clk(int dev_index, unsigned int div)
+{
+ void *addr;
+ unsigned int val, shift;
+
+ addr = &exynos_clock->clk_div_fsys1;
+ shift = dev_index * 10;
+
+ val = readl(addr);
+ val &= ~(0x3ff << shift);
+ val |= (div & 0x3ff) << shift;
+ writel(val, addr);
+}
+
+/* Set DW MMC Controller clock */
+int clock_set_dwmci(enum periph_id peripheral)
+{
+ /* Request MMC clock value to 52MHz. */
+ const unsigned long freq = 52000000;
+ unsigned long sdclkin, cclkin;
+ int device_index = (int)peripheral - (int)PERIPH_ID_SDMMC0;
+
+ ASSERT(device_index >= 0 && device_index < 4);
+ sdclkin = get_mmc_clk(device_index);
+ if (!sdclkin) {
+ return -1;
+ }
+
+ /* The SDCLKIN is divided insided controller by the DIVRATIO field in
+ * CLKSEL register, so we must calculate clock value as
+ * cclk_in = SDCLKIN / (DIVRATIO + 1)
+ * Currently the RIVRATIO must be 3 for MMC0 and MMC2 on Exynos5420
+ * (and must be configured in payload).
+ */
+ if (device_index == 0 || device_index == 2){
+ int divratio = 3;
+ sdclkin /= (divratio + 1);
+ }
+ printk(BIOS_DEBUG, "%s(%d): sdclkin: %ld\n", __func__, device_index, sdclkin);
+
+ cclkin = CEIL_DIV(sdclkin, freq);
+ set_mmc_clk(device_index, cclkin);
+ return 0;
+}
+
+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 peipherals 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->clk_div_peric4;
+ shift = 8;
+ break;
+ case PERIPH_ID_SPI1:
+ reg = &exynos_clock->clk_div_peric4;
+ shift = 16;
+ break;
+ case PERIPH_ID_SPI2:
+ reg = &exynos_clock->clk_div_peric4;
+ shift = 24;
+ break;
+ case PERIPH_ID_SPI3:
+ reg = &exynos_clock->clk_div_isp1;
+ shift = 0;
+ break;
+ case PERIPH_ID_SPI4:
+ reg = &exynos_clock->clk_div_isp1;
+ shift = 8;
+ 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 = 0xf;
+ u32 *reg;
+
+ switch (periph_id) {
+ case PERIPH_ID_SPI0:
+ reg = &exynos_clock->clk_div_peric1;
+ shift = 20;
+ break;
+ case PERIPH_ID_SPI1:
+ reg = &exynos_clock->clk_div_peric1;
+ shift = 24;
+ break;
+ case PERIPH_ID_SPI2:
+ reg = &exynos_clock->clk_div_peric1;
+ shift = 28;
+ break;
+ case PERIPH_ID_SPI3:
+ reg = &exynos_clock->clk_div_isp1;
+ shift = 16;
+ break;
+ case PERIPH_ID_SPI4:
+ reg = &exynos_clock->clk_div_isp1;
+ shift = 20;
+ 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->clk_div_fsys1;
+ break;
+ case PERIPH_ID_SDMMC2:
+ addr = &exynos_clock->clk_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 genarate 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->clk_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 requency 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->clk_div_peric4, AUDIO_1_RATIO_MASK,
+ (div & AUDIO_1_RATIO_MASK));
+ return 0;
+}