sun6i: clock: Add support for the mipi pll

Add support for the mipi pll, this is necessary for getting higher dotclocks
with lcd panels.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>

arch/arm/cpu/armv7/sunxi/clock_sun6i.c

@@ -170,6 +170,47 @@ void clock_set_pll5(unsigned int clk, bool sigma_delta_enable)
 	udelay(5500);
 }
 
+#ifdef CONFIG_MACH_SUN6I
+void clock_set_mipi_pll(unsigned int clk)
+{
+	struct sunxi_ccm_reg * const ccm =
+		(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
+	unsigned int k, m, n, value, diff;
+	unsigned best_k = 0, best_m = 0, best_n = 0, best_diff = 0xffffffff;
+	unsigned int src = clock_get_pll3();
+
+	/* All calculations are in KHz to avoid overflows */
+	clk /= 1000;
+	src /= 1000;
+
+	/* Pick the closest lower clock */
+	for (k = 1; k <= 4; k++) {
+		for (m = 1; m <= 16; m++) {
+			for (n = 1; n <= 16; n++) {
+				value = src * n * k / m;
+				if (value > clk)
+					continue;
+
+				diff = clk - value;
+				if (diff < best_diff) {
+					best_diff = diff;
+					best_k = k;
+					best_m = m;
+					best_n = n;
+				}
+				if (diff == 0)
+					goto done;
+			}
+		}
+	}
+
+done:
+	writel(CCM_MIPI_PLL_CTRL_EN | CCM_MIPI_PLL_CTRL_LDO_EN |
+	       CCM_MIPI_PLL_CTRL_N(best_n) | CCM_MIPI_PLL_CTRL_K(best_k) |
+	       CCM_MIPI_PLL_CTRL_M(best_m), &ccm->mipi_pll_cfg);
+}
+#endif
+
 #ifdef CONFIG_MACH_SUN8I_A33
 void clock_set_pll11(unsigned int clk, bool sigma_delta_enable)
 {
@@ -210,6 +251,20 @@ unsigned int clock_get_pll6(void)
 	return 24000000 * n * k / 2;
 }
 
+unsigned int clock_get_mipi_pll(void)
+{
+	struct sunxi_ccm_reg *const ccm =
+		(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
+	uint32_t rval = readl(&ccm->mipi_pll_cfg);
+	unsigned int n = ((rval & CCM_MIPI_PLL_CTRL_N_MASK) >> CCM_MIPI_PLL_CTRL_N_SHIFT) + 1;
+	unsigned int k = ((rval & CCM_MIPI_PLL_CTRL_K_MASK) >> CCM_MIPI_PLL_CTRL_K_SHIFT) + 1;
+	unsigned int m = ((rval & CCM_MIPI_PLL_CTRL_M_MASK) >> CCM_MIPI_PLL_CTRL_M_SHIFT) + 1;
+	unsigned int src = clock_get_pll3();
+
+	/* Multiply by 1000 after dividing by m to avoid integer overflows */
+	return ((src / 1000) * n * k / m) * 1000;
+}
+
 void clock_set_de_mod_clock(u32 *clk_cfg, unsigned int hz)
 {
 	int pll = clock_get_pll6() * 2;

arch/arm/include/asm/arch-sunxi/clock_sun4i.h

@@ -289,6 +289,7 @@ struct sunxi_ccm_reg {
 #define CCM_LCD_CH0_CTRL_PLL7		(1 << 24)
 #define CCM_LCD_CH0_CTRL_PLL3_2X	(2 << 24)
 #define CCM_LCD_CH0_CTRL_PLL7_2X	(3 << 24)
+#define CCM_LCD_CH0_CTRL_MIPI_PLL	0 /* No mipi pll on sun4i/5i/7i */
 #ifdef CONFIG_MACH_SUN5I
 #define CCM_LCD_CH0_CTRL_TVE_RST	(0x1 << 29)
 #else

arch/arm/include/asm/arch-sunxi/clock_sun6i.h

@@ -202,6 +202,18 @@ struct sunxi_ccm_reg {
 #define CCM_PLL6_CTRL_K_SHIFT		4
 #define CCM_PLL6_CTRL_K_MASK		(0x3 << CCM_PLL6_CTRL_K_SHIFT)
 
+#define CCM_MIPI_PLL_CTRL_M_SHIFT	0
+#define CCM_MIPI_PLL_CTRL_M_MASK	(0xf << CCM_MIPI_PLL_CTRL_M_SHIFT)
+#define CCM_MIPI_PLL_CTRL_M(n)		((((n) - 1) & 0xf) << 0)
+#define CCM_MIPI_PLL_CTRL_K_SHIFT	4
+#define CCM_MIPI_PLL_CTRL_K_MASK	(0x3 << CCM_MIPI_PLL_CTRL_K_SHIFT)
+#define CCM_MIPI_PLL_CTRL_K(n)		((((n) - 1) & 0x3) << 4)
+#define CCM_MIPI_PLL_CTRL_N_SHIFT	8
+#define CCM_MIPI_PLL_CTRL_N_MASK	(0xf << CCM_MIPI_PLL_CTRL_N_SHIFT)
+#define CCM_MIPI_PLL_CTRL_N(n)		((((n) - 1) & 0xf) << 8)
+#define CCM_MIPI_PLL_CTRL_LDO_EN	(0x3 << 22)
+#define CCM_MIPI_PLL_CTRL_EN		(0x1 << 31)
+
 #define CCM_PLL11_CTRL_N(n)		((((n) - 1) & 0x3f) << 8)
 #define CCM_PLL11_CTRL_SIGMA_DELTA_EN	(0x1 << 24)
 #define CCM_PLL11_CTRL_UPD		(0x1 << 30)
@@ -364,8 +376,10 @@ void clock_set_pll1(unsigned int hz);
 void clock_set_pll3(unsigned int hz);
 void clock_set_pll5(unsigned int clk, bool sigma_delta_enable);
 void clock_set_pll11(unsigned int clk, bool sigma_delta_enable);
+void clock_set_mipi_pll(unsigned int hz);
 unsigned int clock_get_pll3(void);
 unsigned int clock_get_pll6(void);
+unsigned int clock_get_mipi_pll(void);
 #endif
 
 #endif /* _SUNXI_CLOCK_SUN6I_H */