rockchip: rk3399: Add support i2s

This patch enable and configure the clocks and IOMUX for i2s audio path,
and the i2s0 clock is from CPLL.

Please refer to TRM V0.3 Part 1 Chapter 3 CRU, P126/P128/P144/P154/P155
for the i2s clock div and gate setting.

BRANCH=none
BUG=chrome-os-partner:52172
TEST=boot kevin rev1, press ctrl+u and hear the beep voice.

Change-Id: Id00baac965c8b9213270ba5516e1ca684e4304a6
Signed-off-by: Martin Roth <martinroth@chromium.org>
Original-Commit-Id: 9c58fa7
Original-Change-Id: I130a874a0400712317e5e7a8b3b10a6f04586f68
Original-Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/347526
Original-Commit-Ready: Wonjoon Lee <woojoo.lee@samsung.com>
Original-Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: https://review.coreboot.org/15034
Tested-by: build bot (Jenkins)
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/mainboard/google/gru/mainboard.c

@@ -92,6 +92,23 @@ static void configure_sdmmc(void)
 	write32(&rk3399_grf->iomux_sdmmc, IOMUX_SDMMC);
 }
 
+static void configure_codec(void)
+{
+	write32(&rk3399_grf->iomux_i2s0, IOMUX_I2S0);
+	write32(&rk3399_grf->iomux_i2sclk, IOMUX_I2SCLK);
+
+	/* AUDIO IO domain 1.8V voltage selection */
+	write32(&rk3399_grf->io_vsel, RK_SETBITS(1 << 1));
+
+	/* CPU1_P1.8V_AUDIO_PWREN for P1.8_AUDIO */
+	gpio_output(GPIO(0, A, 2), 1);
+
+	/* set CPU1_SPK_PA_EN output */
+	gpio_output(GPIO(1, A, 2), 0);
+
+	rkclk_configure_i2s(12288000);
+}
+
 static void configure_display(void)
 {
 	/* set pinmux for edp HPD*/
@@ -105,6 +122,7 @@ static void mainboard_init(device_t dev)
 {
 	configure_sdmmc();
 	configure_emmc();
+	configure_codec();
 	configure_display();
 }
 

src/soc/rockchip/rk3399/clock.c

@@ -686,6 +686,50 @@ uint32_t rkclk_i2c_clock_for_bus(unsigned bus)
 	return freq;
 }
 
+static u32 clk_gcd(u32 a, u32 b)
+{
+	while (b != 0) {
+		int r = b;
+		b = a % b;
+		a = r;
+	}
+	return a;
+}
+
+void rkclk_configure_i2s(unsigned int hz)
+{
+	int n, d;
+	int v;
+
+	/**
+	 * clk_i2s0_sel: divider ouput from fraction
+	 * clk_i2s0_pll_sel source clock: cpll
+	 * clk_i2s0_div_con: 1 (div+1)
+	 */
+	write32(&cru_ptr->clksel_con[28],
+		RK_CLRSETBITS(3 << 8 | 1 << 7 | 0x7f << 0,
+			      1 << 8 | 0 << 7 | 0 << 0));
+
+	/* make sure and enable i2s0 path gates */
+	write32(&cru_ptr->clkgate_con[8],
+		RK_CLRBITS(1 << 12 | 1 << 5 | 1 << 4 | 1 << 3));
+
+	/* set frac divider */
+	v = clk_gcd(CPLL_HZ, hz);
+	n = (CPLL_HZ / v) & (0xffff);
+	d = (hz / v) & (0xffff);
+	assert(hz == CPLL_HZ / n * d);
+	write32(&cru_ptr->clksel_con[96], d << 16 | n);
+
+	/**
+	 * clk_i2sout_sel clk_i2s
+	 * clk_i2s_ch_sel: clk_i2s0
+	 */
+	write32(&cru_ptr->clksel_con[31],
+		RK_CLRSETBITS(1 << 2 | 3 << 0,
+			      0 << 2 | 0 << 0));
+}
+
 void rkclk_configure_saradc(unsigned int hz)
 {
 	int src_clk_div;

src/soc/rockchip/rk3399/include/soc/clock.h

@@ -107,6 +107,7 @@ int rkclk_configure_vop_dclk(u32 vop_id, u32 dclk_hz);
 void rkclk_configure_cpu(enum apll_l_frequencies apll_l_freq);
 void rkclk_configure_ddr(unsigned int hz);
 void rkclk_configure_emmc(void);
+void rkclk_configure_i2s(unsigned int hz);
 void rkclk_configure_saradc(unsigned int hz);
 void rkclk_configure_spi(unsigned int bus, unsigned int hz);
 void rkclk_configure_tsadc(unsigned int hz);

src/soc/rockchip/rk3399/include/soc/grf.h

@@ -131,8 +131,14 @@ struct rk3399_grf_regs {
 	u32 gpio3a_iomux;
 	u32 gpio3b_iomux;
 	u32 gpio3c_iomux;
+	union {
+		u32 iomux_i2s0;
 		u32 gpio3d_iomux;
+	};
+	union {
+		u32 iomux_i2sclk;
 		u32 gpio4a_iomux;
+	};
 	union {
 		u32 iomux_sdmmc;
 		u32 iomux_uart2a;
@@ -346,6 +352,11 @@ static struct rk3399_pmusgrf_regs * const rk3399_pmusgrf = (void *)PMUSGRF_BASE;
 					     1 << 4 | 1 << 2 | 1 << 0)
 #define IOMUX_I2C0_SCL	RK_CLRSETBITS(3 << 0, 2 << 0)
 #define IOMUX_I2C0_SDA	RK_CLRSETBITS(3 << 14, 2 << 14)
+
+#define IOMUX_I2S0	RK_SETBITS(1 << 14 | 1 << 12 | 1 << 10 | 1 << 8 |\
+				   1 << 6 | 1 << 4 | 1 << 2 | 1 << 0)
+#define IOMUX_I2SCLK	RK_SETBITS(1 << 0)
+
 #define IOMUX_PWM_0	RK_SETBITS(1 << 4)
 #define IOMUX_PWM_1	RK_SETBITS(1 << 12)
 #define IOMUX_PWM_2	RK_SETBITS(1 << 6)