[PATCH 3/6] OMAP2/3 clock: move DPLL bypass rate calculation into omap2_get_dpll_rate()

[Paul Walmsley <paul@pwsan.com>]

Removes the clksel-based DPLL rate handling from the OMAP3 clock tree.
In its place, omap2_get_dpll_rate() now has code to determine whether the DPLL
is bypassed.  This obsoletes several clocks, which are removed by this patch.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
---
 arch/arm/mach-omap2/clock.c     |   45 +++++++++-
 arch/arm/mach-omap2/clock24xx.c |    4 +
 arch/arm/mach-omap2/clock24xx.h |    2 
 arch/arm/mach-omap2/clock34xx.h |  169 +++------------------------------------
 4 files changed, 58 insertions(+), 162 deletions(-)

diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c
index 5f48e14..a2211fb 100644
--- a/arch/arm/mach-omap2/clock.c
+++ b/arch/arm/mach-omap2/clock.c
@@ -60,6 +60,10 @@
 #define DPLL_ROUNDING_VAL		((DPLL_SCALE_BASE / 2) * \
 					 (DPLL_SCALE_FACTOR / DPLL_SCALE_BASE))
 
+/* Some OMAP2xxx CM_CLKSEL_PLL.ST_CORE_CLK bits - for omap2_get_dpll_rate() */
+#define ST_CORE_CLK_REF			0x1
+#define ST_CORE_CLK_32K			0x3
+
 u8 cpu_mask;
 
 /*-------------------------------------------------------------------------
@@ -137,22 +141,51 @@ void omap2_init_clksel_parent(struct clk *clk)
 	return;
 }
 
-/* Returns the DPLL rate */
+/**
+ * omap2_get_dpll_rate - returns the current DPLL CLKOUT rate
+ * @clk: struct clk * of a DPLL
+ *
+ * DPLLs can be locked or bypassed - basically, enabled or disabled.
+ * When locked, the DPLL output depends on the M and N values.  When
+ * bypassed, on OMAP2xxx, the output rate is either the 32KiHz clock
+ * or sys_clk.  Bypass rates on OMAP3 depend on the DPLL: DPLLs 1 and
+ * 2 are bypassed with dpll1_fclk and dpll2_fclk respectively
+ * (generated by DPLL3), while DPLL 3, 4, and 5 bypass rates are sys_clk.
+ * Returns the current DPLL CLKOUT rate (*not* CLKOUTX2) if the DPLL is
+ * locked, or the appropriate bypass rate if the DPLL is bypassed, or 0
+ * if the clock @clk is not a DPLL.
+ */
 u32 omap2_get_dpll_rate(struct clk *clk)
 {
 	long long dpll_clk;
-	u32 dpll_mult, dpll_div, dpll;
+	u32 dpll_mult, dpll_div, v;
 	struct dpll_data *dd;
 
 	dd = clk->dpll_data;
-	/* REVISIT: What do we return on error? */
 	if (!dd)
 		return 0;
 
-	dpll = __raw_readl(dd->mult_div1_reg);
-	dpll_mult = dpll & dd->mult_mask;
+	/* Return bypass rate if DPLL is bypassed */
+	v = __raw_readl(dd->idlest_reg) & dd->idlest_mask;
+	v >>= __ffs(dd->idlest_mask);
+	if (cpu_is_omap24xx()) {
+
+		if (v == ST_CORE_CLK_REF)
+			return clk->parent->rate; /* sys_clk */
+		else if (v == ST_CORE_CLK_32K)
+			return 32768;
+
+	} else if (cpu_is_omap34xx()) {
+
+		if (!v)
+			return clk->parent->rate;
+
+	}
+
+	v = __raw_readl(dd->mult_div1_reg);
+	dpll_mult = v & dd->mult_mask;
 	dpll_mult >>= __ffs(dd->mult_mask);
-	dpll_div = dpll & dd->div1_mask;
+	dpll_div = v & dd->div1_mask;
 	dpll_div >>= __ffs(dd->div1_mask);
 
 	dpll_clk = (long long)clk->parent->rate * dpll_mult;
diff --git a/arch/arm/mach-omap2/clock24xx.c b/arch/arm/mach-omap2/clock24xx.c
index c26d9d8..ddb6429 100644
--- a/arch/arm/mach-omap2/clock24xx.c
+++ b/arch/arm/mach-omap2/clock24xx.c
@@ -535,8 +535,10 @@ static void __init omap2_clk_rewrite_base(struct clk *clk)
 {
 	omap2_clk_check_reg(clk->flags, &clk->clksel_reg);
 	omap2_clk_check_reg(clk->flags, &clk->enable_reg);
-	if (clk->dpll_data)
+	if (clk->dpll_data) {
 		omap2_clk_check_reg(0, &clk->dpll_data->mult_div1_reg);
+		omap2_clk_check_reg(0, &clk->dpll_data->idlest_reg);
+	}
 }
 
 int __init omap2_clk_init(void)
diff --git a/arch/arm/mach-omap2/clock24xx.h b/arch/arm/mach-omap2/clock24xx.h
index 63349fa..775d08b 100644
--- a/arch/arm/mach-omap2/clock24xx.h
+++ b/arch/arm/mach-omap2/clock24xx.h
@@ -682,6 +682,8 @@ static struct dpll_data dpll_dd = {
 	.mult_div1_reg		= _CM_REG_OFFSET(PLL_MOD, CM_CLKSEL1),
 	.mult_mask		= OMAP24XX_DPLL_MULT_MASK,
 	.div1_mask		= OMAP24XX_DPLL_DIV_MASK,
+	.idlest_reg		= _CM_REG_OFFSET(PLL_MOD, CM_IDLEST),
+	.idlest_mask		= OMAP24XX_ST_CORE_CLK_MASK,
 	.max_multiplier		= 1024,
 	.max_divider		= 16,
 	.rate_tolerance		= DEFAULT_DPLL_RATE_TOLERANCE
diff --git a/arch/arm/mach-omap2/clock34xx.h b/arch/arm/mach-omap2/clock34xx.h
index 19c3881..3ee60bc 100644
--- a/arch/arm/mach-omap2/clock34xx.h
+++ b/arch/arm/mach-omap2/clock34xx.h
@@ -257,16 +257,6 @@ static struct clk sys_clkout1 = {
 
 /* CM CLOCKS */
 
-static const struct clksel_rate dpll_bypass_rates[] = {
-	{ .div = 1, .val = 0, .flags = RATE_IN_343X | DEFAULT_RATE },
-	{ .div = 0 }
-};
-
-static const struct clksel_rate dpll_locked_rates[] = {
-	{ .div = 1, .val = 1, .flags = RATE_IN_343X | DEFAULT_RATE },
-	{ .div = 0 }
-};
-
 static const struct clksel_rate div16_dpll_rates[] = {
 	{ .div = 1, .val = 1, .flags = RATE_IN_343X | DEFAULT_RATE },
 	{ .div = 2, .val = 2, .flags = RATE_IN_343X },
@@ -527,40 +517,22 @@ static struct clk dpll3_m2_ck = {
 	.recalc		= &omap2_clksel_recalc,
 };
 
-static const struct clksel core_ck_clksel[] = {
-	{ .parent = &sys_ck,	  .rates = dpll_bypass_rates },
-	{ .parent = &dpll3_m2_ck, .rates = dpll_locked_rates },
-	{ .parent = NULL }
-};
-
 static struct clk core_ck = {
 	.name		= "core_ck",
-	.init		= &omap2_init_clksel_parent,
-	.clksel_reg	= _OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST),
-	.clksel_mask	= OMAP3430_ST_CORE_CLK_MASK,
-	.clksel		= core_ck_clksel,
+	.parent		= &dpll3_m2_ck,
 	.flags		= CLOCK_IN_OMAP343X | RATE_PROPAGATES |
 				PARENT_CONTROLS_CLOCK,
 	.clkdm		= { .name = "cm_clkdm" },
-	.recalc		= &omap2_clksel_recalc,
-};
-
-static const struct clksel dpll3_m2x2_ck_clksel[] = {
-	{ .parent = &sys_ck,	  .rates = dpll_bypass_rates },
-	{ .parent = &dpll3_x2_ck, .rates = dpll_locked_rates },
-	{ .parent = NULL }
+	.recalc		= &followparent_recalc,
 };
 
 static struct clk dpll3_m2x2_ck = {
 	.name		= "dpll3_m2x2_ck",
-	.init		= &omap2_init_clksel_parent,
-	.clksel_reg	= _OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST),
-	.clksel_mask	= OMAP3430_ST_CORE_CLK_MASK,
-	.clksel		= dpll3_m2x2_ck_clksel,
+	.parent		= &dpll3_x2_ck,
 	.flags		= CLOCK_IN_OMAP343X | RATE_PROPAGATES |
 				PARENT_CONTROLS_CLOCK,
 	.clkdm		= { .name = "dpll3_clkdm" },
-	.recalc		= &omap2_clksel_recalc,
+	.recalc		= &followparent_recalc,
 };
 
 /* The PWRDN bit is apparently only available on 3430ES2 and above */
@@ -594,23 +566,13 @@ static struct clk dpll3_m3x2_ck = {
 	.recalc		= &omap3_clkoutx2_recalc,
 };
 
-static const struct clksel emu_core_alwon_ck_clksel[] = {
-	{ .parent = &sys_ck,	    .rates = dpll_bypass_rates },
-	{ .parent = &dpll3_m3x2_ck, .rates = dpll_locked_rates },
-	{ .parent = NULL }
-};
-
 static struct clk emu_core_alwon_ck = {
 	.name		= "emu_core_alwon_ck",
 	.parent		= &dpll3_m3x2_ck,
-	.init		= &omap2_init_clksel_parent,
-	.clksel_reg	= _OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST),
-	.clksel_mask	= OMAP3430_ST_CORE_CLK_MASK,
-	.clksel		= emu_core_alwon_ck_clksel,
 	.flags		= CLOCK_IN_OMAP343X | RATE_PROPAGATES |
 				PARENT_CONTROLS_CLOCK,
 	.clkdm		= { .name = "dpll3_clkdm" },
-	.recalc		= &omap2_clksel_recalc,
+	.recalc		= &followparent_recalc,
 };
 
 /* DPLL4 */
@@ -693,12 +655,6 @@ static struct clk dpll4_m2x2_ck = {
 	.recalc		= &omap3_clkoutx2_recalc,
 };
 
-static const struct clksel omap_96m_alwon_fck_clksel[] = {
-	{ .parent = &sys_ck,	    .rates = dpll_bypass_rates },
-	{ .parent = &dpll4_m2x2_ck, .rates = dpll_locked_rates },
-	{ .parent = NULL }
-};
-
 /*
  * DPLL4 generates DPLL4_M2X2_CLK which is then routed into the PRM as
  * PRM_96M_ALWON_(F)CLK.  Two clocks then emerge from the PRM:
@@ -708,14 +664,10 @@ static const struct clksel omap_96m_alwon_fck_clksel[] = {
 static struct clk omap_96m_alwon_fck = {
 	.name		= "omap_96m_alwon_fck",
 	.parent		= &dpll4_m2x2_ck,
-	.init		= &omap2_init_clksel_parent,
-	.clksel_reg	= _OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST),
-	.clksel_mask	= OMAP3430_ST_PERIPH_CLK_MASK,
-	.clksel		= omap_96m_alwon_fck_clksel,
 	.flags		= CLOCK_IN_OMAP343X | RATE_PROPAGATES |
 				PARENT_CONTROLS_CLOCK,
 	.clkdm		= { .name = "prm_clkdm" },
-	.recalc		= &omap2_clksel_recalc,
+	.recalc		= &followparent_recalc,
 };
 
 static struct clk cm_96m_fck = {
@@ -782,25 +734,6 @@ static struct clk dpll4_m3x2_ck = {
 	.recalc		= &omap3_clkoutx2_recalc,
 };
 
-static const struct clksel virt_omap_54m_fck_clksel[] = {
-	{ .parent = &sys_ck,	    .rates = dpll_bypass_rates },
-	{ .parent = &dpll4_m3x2_ck, .rates = dpll_locked_rates },
-	{ .parent = NULL }
-};
-
-static struct clk virt_omap_54m_fck = {
-	.name		= "virt_omap_54m_fck",
-	.parent		= &dpll4_m3x2_ck,
-	.init		= &omap2_init_clksel_parent,
-	.clksel_reg	= _OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST),
-	.clksel_mask	= OMAP3430_ST_PERIPH_CLK_MASK,
-	.clksel		= virt_omap_54m_fck_clksel,
-	.flags		= CLOCK_IN_OMAP343X | RATE_PROPAGATES |
-				PARENT_CONTROLS_CLOCK,
-	.clkdm		= { .name = "dpll4_clkdm" },
-	.recalc		= &omap2_clksel_recalc,
-};
-
 static const struct clksel_rate omap_54m_d4m3x2_rates[] = {
 	{ .div = 1, .val = 0, .flags = RATE_IN_343X | DEFAULT_RATE },
 	{ .div = 0 }
@@ -812,7 +745,7 @@ static const struct clksel_rate omap_54m_alt_rates[] = {
 };
 
 static const struct clksel omap_54m_clksel[] = {
-	{ .parent = &virt_omap_54m_fck, .rates = omap_54m_d4m3x2_rates },
+	{ .parent = &dpll4_m3x2_ck, .rates = omap_54m_d4m3x2_rates },
 	{ .parent = &sys_altclk,    .rates = omap_54m_alt_rates },
 	{ .parent = NULL }
 };
@@ -1007,25 +940,6 @@ static struct clk dpll5_m2_ck = {
 	.recalc		= &omap2_clksel_recalc,
 };
 
-static const struct clksel omap_120m_fck_clksel[] = {
-	{ .parent = &sys_ck,	  .rates = dpll_bypass_rates },
-	{ .parent = &dpll5_m2_ck, .rates = dpll_locked_rates },
-	{ .parent = NULL }
-};
-
-static struct clk omap_120m_fck = {
-	.name		= "omap_120m_fck",
-	.parent		= &dpll5_m2_ck,
-	.init		= &omap2_init_clksel_parent,
-	.clksel_reg	= _OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST2),
-	.clksel_mask	= OMAP3430ES2_ST_PERIPH2_CLK_MASK,
-	.clksel		= omap_120m_fck_clksel,
-	.flags		= CLOCK_IN_OMAP3430ES2 | RATE_PROPAGATES |
-				PARENT_CONTROLS_CLOCK,
-	.clkdm		= { .name = "dpll5_clkdm" },
-	.recalc		= &omap2_clksel_recalc,
-};
-
 /* CM EXTERNAL CLOCK OUTPUTS */
 
 static const struct clksel_rate clkout2_src_core_rates[] = {
@@ -1132,29 +1046,13 @@ static struct clk dpll1_fck = {
 	.recalc		= &omap2_clksel_recalc,
 };
 
-/*
- * MPU clksel:
- * If DPLL1 is locked, mpu_ck derives from DPLL1; otherwise, mpu_ck
- * derives from the high-frequency bypass clock originating from DPLL3,
- * called 'dpll1_fck'
- */
-static const struct clksel mpu_clksel[] = {
-	{ .parent = &dpll1_fck,	    .rates = dpll_bypass_rates },
-	{ .parent = &dpll1_x2m2_ck, .rates = dpll_locked_rates },
-	{ .parent = NULL }
-};
-
 static struct clk mpu_ck = {
 	.name		= "mpu_ck",
 	.parent		= &dpll1_x2m2_ck,
-	.init		= &omap2_init_clksel_parent,
-	.clksel_reg	= _OMAP34XX_CM_REGADDR(MPU_MOD, OMAP3430_CM_IDLEST_PLL),
-	.clksel_mask	= OMAP3430_ST_MPU_CLK_MASK,
-	.clksel		= mpu_clksel,
 	.flags		= CLOCK_IN_OMAP343X | RATE_PROPAGATES |
 				PARENT_CONTROLS_CLOCK,
 	.clkdm		= { .name = "mpu_clkdm" },
-	.recalc		= &omap2_clksel_recalc,
+	.recalc		= &followparent_recalc,
 };
 
 /* arm_fck is divided by two when DPLL1 locked; otherwise, passthrough mpu_ck */
@@ -1210,32 +1108,15 @@ static struct clk dpll2_fck = {
 	.recalc		= &omap2_clksel_recalc,
 };
 
-/*
- * IVA2 clksel:
- * If DPLL2 is locked, iva2_ck derives from DPLL2; otherwise, iva2_ck
- * derives from the high-frequency bypass clock originating from DPLL3,
- * called 'dpll2_fck'
- */
-
-static const struct clksel iva2_clksel[] = {
-	{ .parent = &dpll2_fck,	  .rates = dpll_bypass_rates },
-	{ .parent = &dpll2_m2_ck, .rates = dpll_locked_rates },
-	{ .parent = NULL }
-};
-
 static struct clk iva2_ck = {
 	.name		= "iva2_ck",
 	.parent		= &dpll2_m2_ck,
 	.init		= &omap2_init_clksel_parent,
 	.enable_reg	= _OMAP34XX_CM_REGADDR(OMAP3430_IVA2_MOD, CM_FCLKEN),
 	.enable_bit	= OMAP3430_CM_FCLKEN_IVA2_EN_IVA2_SHIFT,
-	.clksel_reg	= _OMAP34XX_CM_REGADDR(OMAP3430_IVA2_MOD,
-					  OMAP3430_CM_IDLEST_PLL),
-	.clksel_mask	= OMAP3430_ST_IVA2_CLK_MASK,
-	.clksel		= iva2_clksel,
 	.flags		= CLOCK_IN_OMAP343X | RATE_PROPAGATES,
 	.clkdm		= { .name = "iva2_clkdm" },
-	.recalc		= &omap2_clksel_recalc,
+	.recalc		= &followparent_recalc,
 };
 
 /* Common interface clocks */
@@ -1467,7 +1348,7 @@ static struct clk ts_fck = {
 
 static struct clk usbtll_fck = {
 	.name		= "usbtll_fck",
-	.parent		= &omap_120m_fck,
+	.parent		= &dpll5_m2_ck,
 	.enable_reg	= _OMAP34XX_CM_REGADDR(CORE_MOD, OMAP3430ES2_CM_FCLKEN3),
 	.enable_bit	= OMAP3430ES2_EN_USBTLL_SHIFT,
 	.flags		= CLOCK_IN_OMAP3430ES2,
@@ -2203,24 +2084,14 @@ static struct clk des1_ick = {
 };
 
 /* DSS */
-static const struct clksel dss1_alwon_fck_clksel[] = {
-	{ .parent = &sys_ck,	    .rates = dpll_bypass_rates },
-	{ .parent = &dpll4_m4x2_ck, .rates = dpll_locked_rates },
-	{ .parent = NULL }
-};
-
 static struct clk dss1_alwon_fck = {
 	.name		= "dss1_alwon_fck",
 	.parent		= &dpll4_m4x2_ck,
-	.init		= &omap2_init_clksel_parent,
 	.enable_reg	= _OMAP34XX_CM_REGADDR(OMAP3430_DSS_MOD, CM_FCLKEN),
 	.enable_bit	= OMAP3430_EN_DSS1_SHIFT,
-	.clksel_reg	= _OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST),
-	.clksel_mask	= OMAP3430_ST_PERIPH_CLK_MASK,
-	.clksel		= dss1_alwon_fck_clksel,
 	.flags		= CLOCK_IN_OMAP343X,
 	.clkdm		= { .name = "dss_clkdm" },
-	.recalc		= &omap2_clksel_recalc,
+	.recalc		= &followparent_recalc,
 };
 
 static struct clk dss_tv_fck = {
@@ -2266,24 +2137,14 @@ static struct clk dss_ick = {
 
 /* CAM */
 
-static const struct clksel cam_mclk_clksel[] = {
-	{ .parent = &sys_ck,	    .rates = dpll_bypass_rates },
-	{ .parent = &dpll4_m5x2_ck, .rates = dpll_locked_rates },
-	{ .parent = NULL }
-};
-
 static struct clk cam_mclk = {
 	.name		= "cam_mclk",
 	.parent		= &dpll4_m5x2_ck,
-	.init		= &omap2_init_clksel_parent,
-	.clksel_reg	= _OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST),
-	.clksel_mask	= OMAP3430_ST_PERIPH_CLK_MASK,
-	.clksel		= cam_mclk_clksel,
 	.enable_reg	= _OMAP34XX_CM_REGADDR(OMAP3430_CAM_MOD, CM_FCLKEN),
 	.enable_bit	= OMAP3430_EN_CAM_SHIFT,
 	.flags		= CLOCK_IN_OMAP343X,
 	.clkdm		= { .name = "cam_clkdm" },
-	.recalc		= &omap2_clksel_recalc,
+	.recalc		= &followparent_recalc,
 };
 
 static struct clk cam_ick = {
@@ -2311,7 +2172,7 @@ static struct clk csi2_96m_fck = {
 
 static struct clk usbhost_120m_fck = {
 	.name		= "usbhost_120m_fck",
-	.parent		= &omap_120m_fck,
+	.parent		= &dpll5_m2_ck,
 	.enable_reg	= _OMAP34XX_CM_REGADDR(OMAP3430ES2_USBHOST_MOD, CM_FCLKEN),
 	.enable_bit	= OMAP3430ES2_EN_USBHOST2_SHIFT,
 	.flags		= CLOCK_IN_OMAP3430ES2,
@@ -2360,7 +2221,7 @@ static const struct clksel_rate usim_120m_rates[] = {
 
 static const struct clksel usim_clksel[] = {
 	{ .parent = &omap_96m_fck,	.rates = usim_96m_rates },
-	{ .parent = &omap_120m_fck,	.rates = usim_120m_rates },
+	{ .parent = &dpll5_m2_ck,	.rates = usim_120m_rates },
 	{ .parent = &sys_ck,		.rates = div2_rates },
 	{ .parent = NULL },
 };
@@ -3172,7 +3033,6 @@ static struct clk *onchip_34xx_clks[] __initdata = {
 	&omap_96m_alwon_fck,
 	&omap_96m_fck,
 	&cm_96m_fck,
-	&virt_omap_54m_fck,
 	&omap_54m_fck,
 	&omap_48m_fck,
 	&omap_12m_fck,
@@ -3189,7 +3049,6 @@ static struct clk *onchip_34xx_clks[] __initdata = {
 	&emu_per_alwon_ck,
 	&dpll5_ck,
 	&dpll5_m2_ck,
-	&omap_120m_fck,
 	&clkout2_src_ck,
 	&sys_clkout2,
 	&corex2_fck,