+int exynos5_set_epll_clk(unsigned long rate)
+{
+ unsigned int epll_con, epll_con_k;
+ unsigned int i;
+ unsigned int lockcnt;
+ unsigned int start;
+ struct exynos5_clock *clk =
+ (struct exynos5_clock *)samsung_get_base_clock();
+
+ epll_con = readl(&clk->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(exynos5_epll_div); i++) {
+ if (exynos5_epll_div[i].freq_out == rate)
+ break;
+ }
+
+ if (i == ARRAY_SIZE(exynos5_epll_div))
+ return -1;
+
+ epll_con_k = exynos5_epll_div[i].k_dsm << 0;
+ epll_con |= exynos5_epll_div[i].en_lock_det <<
+ EPLL_CON0_LOCK_DET_EN_SHIFT;
+ epll_con |= exynos5_epll_div[i].m_div << EPLL_CON0_MDIV_SHIFT;
+ epll_con |= exynos5_epll_div[i].p_div << EPLL_CON0_PDIV_SHIFT;
+ epll_con |= exynos5_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 * exynos5_epll_div[i].p_div;
+
+ writel(lockcnt, &clk->epll_lock);
+ writel(epll_con, &clk->epll_con0);
+ writel(epll_con_k, &clk->epll_con1);
+
+ start = get_timer(0);
+
+ while (!(readl(&clk->epll_con0) &
+ (0x1 << EXYNOS5_EPLLCON0_LOCKED_SHIFT))) {
+ if (get_timer(start) > TIMEOUT_EPLL_LOCK) {
+ debug("%s: Timeout waiting for EPLL lock\n", __func__);
+ return -1;
+ }
+ }
+ return 0;
+}
+
+void exynos5_set_i2s_clk_source(void)
+{
+ struct exynos5_clock *clk =
+ (struct exynos5_clock *)samsung_get_base_clock();
+
+ clrsetbits_le32(&clk->src_peric1, AUDIO1_SEL_MASK,
+ (CLK_SRC_SCLK_EPLL));
+}
+
+int exynos5_set_i2s_clk_prescaler(unsigned int src_frq,
+ unsigned int dst_frq)
+{
+ struct exynos5_clock *clk =
+ (struct exynos5_clock *)samsung_get_base_clock();
+ unsigned int div;
+
+ if ((dst_frq == 0) || (src_frq == 0)) {
+ debug("%s: Invalid requency input for prescaler\n", __func__);
+ debug("src frq = %d des frq = %d ", src_frq, dst_frq);
+ return -1;
+ }
+
+ div = (src_frq / dst_frq);
+ if (div > AUDIO_1_RATIO_MASK) {
+ debug("%s: Frequency ratio is out of range\n", __func__);
+ debug("src frq = %d des frq = %d ", src_frq, dst_frq);
+ return -1;
+ }
+ clrsetbits_le32(&clk->div_peric4, AUDIO_1_RATIO_MASK,
+ (div & AUDIO_1_RATIO_MASK));
+ return 0;
+}
+
+/**
+ * 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;
+
+ 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;
+
+ 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;
+}
+
+static int exynos5_set_spi_clk(enum periph_id periph_id,
+ unsigned int rate)
+{
+ struct exynos5_clock *clk =
+ (struct exynos5_clock *)samsung_get_base_clock();
+ int main;
+ unsigned int fine;
+ unsigned shift, pre_shift;
+ unsigned mask = 0xff;
+ u32 *reg;
+
+ main = clock_calc_best_scalar(4, 8, 400000000, rate, &fine);
+ if (main < 0) {
+ debug("%s: Cannot set clock rate for periph %d",
+ __func__, periph_id);
+ return -1;
+ }
+ main = main - 1;
+ fine = fine - 1;
+
+ switch (periph_id) {
+ case PERIPH_ID_SPI0:
+ reg = &clk->div_peric1;
+ shift = 0;
+ pre_shift = 8;
+ break;
+ case PERIPH_ID_SPI1:
+ reg = &clk->div_peric1;
+ shift = 16;
+ pre_shift = 24;
+ break;
+ case PERIPH_ID_SPI2:
+ reg = &clk->div_peric2;
+ shift = 0;
+ pre_shift = 8;
+ break;
+ case PERIPH_ID_SPI3:
+ reg = &clk->sclk_div_isp;
+ shift = 0;
+ pre_shift = 4;
+ break;
+ case PERIPH_ID_SPI4:
+ reg = &clk->sclk_div_isp;
+ shift = 12;
+ pre_shift = 16;
+ break;
+ default:
+ debug("%s: Unsupported peripheral ID %d\n", __func__,
+ periph_id);
+ return -1;
+ }
+ clrsetbits_le32(reg, mask << shift, (main & mask) << shift);
+ clrsetbits_le32(reg, mask << pre_shift, (fine & mask) << pre_shift);
+
+ return 0;
+}
+
+static unsigned long exynos4_get_i2c_clk(void)
+{
+ struct exynos4_clock *clk =
+ (struct exynos4_clock *)samsung_get_base_clock();
+ unsigned long sclk, aclk_100;
+ unsigned int ratio;
+
+ sclk = get_pll_clk(APLL);
+
+ ratio = (readl(&clk->div_top)) >> 4;
+ ratio &= 0xf;
+ aclk_100 = sclk / (ratio + 1);
+ return aclk_100;
+}
+