+static int exynos5420_set_spi_clk(enum periph_id periph_id,
+ unsigned int rate)
+{
+ struct exynos5420_clock *clk =
+ (struct exynos5420_clock *)samsung_get_base_clock();
+ int main;
+ unsigned int fine;
+ unsigned shift, pre_shift;
+ unsigned div_mask = 0xf, pre_div_mask = 0xff;
+ u32 *reg;
+ u32 *pre_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 = 20;
+ pre_reg = &clk->div_peric4;
+ pre_shift = 8;
+ break;
+ case PERIPH_ID_SPI1:
+ reg = &clk->div_peric1;
+ shift = 24;
+ pre_reg = &clk->div_peric4;
+ pre_shift = 16;
+ break;
+ case PERIPH_ID_SPI2:
+ reg = &clk->div_peric1;
+ shift = 28;
+ pre_reg = &clk->div_peric4;
+ pre_shift = 24;
+ break;
+ case PERIPH_ID_SPI3:
+ reg = &clk->div_isp1;
+ shift = 16;
+ pre_reg = &clk->div_isp1;
+ pre_shift = 0;
+ break;
+ case PERIPH_ID_SPI4:
+ reg = &clk->div_isp1;
+ shift = 20;
+ pre_reg = &clk->div_isp1;
+ pre_shift = 8;
+ break;
+ default:
+ debug("%s: Unsupported peripheral ID %d\n", __func__,
+ periph_id);
+ return -1;
+ }
+
+ clrsetbits_le32(reg, div_mask << shift, (main & div_mask) << shift);
+ clrsetbits_le32(pre_reg, pre_div_mask << pre_shift,
+ (fine & pre_div_mask) << pre_shift);
+
+ return 0;
+}
+