ARM: davinci: da850: use clk->set_parent for async3

The da850 family of processors has an async3 clock domain that can be
muxed to either pll0_sysclk2 or pll1_sysclk2. Now that the davinci clocks
have a set_parent callback, we can use this to control the async3 mux
instead of a stand-alone function.

This adds a new async3_clk and sets the appropriate child clocks. The
default is use to pll1_sysclk2 since it is not affected by processor
frequency scaling.

Signed-off-by: David Lechner <david@lechnology.com>
[nsekhar@ti.com: drop unnecessary comment]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>

1 files changed, 33 insertions, 48 deletions

diff --git a/arch/arm/mach-davinci/da850.c b/arch/arm/mach-davinci/da850.c
index 1f85bbca2e55..239886299968 100644
--- a/arch/arm/mach-davinci/da850.c
+++ b/arch/arm/mach-davinci/da850.c
@@ -34,9 +34,6 @@
 #include "clock.h"
 #include "mux.h"
 
-/* SoC specific clock flags */
-#define DA850_CLK_ASYNC3        BIT(16)
-
 #define DA850_PLL1_BASE         0x01e1a000
 #define DA850_TIMER64P2_BASE    0x01f0c000
 #define DA850_TIMER64P3_BASE    0x01f0d000
@@ -161,6 +158,32 @@ static struct clk pll1_sysclk3 = {
         .div_reg        = PLLDIV3,
 };
 
+static int da850_async3_set_parent(struct clk *clk, struct clk *parent)
+{
+        u32 val;
+
+        val = readl(DA8XX_SYSCFG0_VIRT(DA8XX_CFGCHIP3_REG));
+
+        if (parent == &pll0_sysclk2) {
+                val &= ~CFGCHIP3_ASYNC3_CLKSRC;
+        } else if (parent == &pll1_sysclk2) {
+                val |= CFGCHIP3_ASYNC3_CLKSRC;
+        } else {
+                pr_err("Bad parent on async3 clock mux\n");
+                return -EINVAL;
+        }
+
+        writel(val, DA8XX_SYSCFG0_VIRT(DA8XX_CFGCHIP3_REG));
+
+        return 0;
+}
+
+static struct clk async3_clk = {
+        .name           = "async3",
+        .parent         = &pll1_sysclk2,
+        .set_parent     = da850_async3_set_parent,
+};
+
 static struct clk i2c0_clk = {
         .name           = "i2c0",
         .parent         = &pll0_aux_clk,
@@ -234,18 +257,16 @@ static struct clk uart0_clk = {
 
 static struct clk uart1_clk = {
         .name           = "uart1",
-        .parent         = &pll0_sysclk2,
+        .parent         = &async3_clk,
         .lpsc           = DA8XX_LPSC1_UART1,
         .gpsc           = 1,
-        .flags          = DA850_CLK_ASYNC3,
 };
 
 static struct clk uart2_clk = {
         .name           = "uart2",
-        .parent         = &pll0_sysclk2,
+        .parent         = &async3_clk,
         .lpsc           = DA8XX_LPSC1_UART2,
         .gpsc           = 1,
-        .flags          = DA850_CLK_ASYNC3,
 };
 
 static struct clk aintc_clk = {
@@ -300,10 +321,9 @@ static struct clk emac_clk = {
 
 static struct clk mcasp_clk = {
         .name           = "mcasp",
-        .parent         = &pll0_sysclk2,
+        .parent         = &async3_clk,
         .lpsc           = DA8XX_LPSC1_McASP0,
         .gpsc           = 1,
-        .flags          = DA850_CLK_ASYNC3,
 };
 
 static struct clk lcdc_clk = {
@@ -355,10 +375,9 @@ static struct clk spi0_clk = {
 
 static struct clk spi1_clk = {
         .name           = "spi1",
-        .parent         = &pll0_sysclk2,
+        .parent         = &async3_clk,
         .lpsc           = DA8XX_LPSC1_SPI1,
         .gpsc           = 1,
-        .flags          = DA850_CLK_ASYNC3,
 };
 
 static struct clk vpif_clk = {
@@ -386,10 +405,9 @@ static struct clk dsp_clk = {
 
 static struct clk ehrpwm_clk = {
         .name           = "ehrpwm",
-        .parent         = &pll0_sysclk2,
+        .parent         = &async3_clk,
         .lpsc           = DA8XX_LPSC1_PWM,
         .gpsc           = 1,
-        .flags          = DA850_CLK_ASYNC3,
 };
 
 #define DA8XX_EHRPWM_TBCLKSYNC  BIT(12)
@@ -421,10 +439,9 @@ static struct clk ehrpwm_tbclk = {
 
 static struct clk ecap_clk = {
         .name           = "ecap",
-        .parent         = &pll0_sysclk2,
+        .parent         = &async3_clk,
         .lpsc           = DA8XX_LPSC1_ECAP,
         .gpsc           = 1,
-        .flags          = DA850_CLK_ASYNC3,
 };
 
 static struct clk_lookup da850_clks[] = {
@@ -442,6 +459,7 @@ static struct clk_lookup da850_clks[] = {
         CLK(NULL,               "pll1_aux",     &pll1_aux_clk),
         CLK(NULL,               "pll1_sysclk2", &pll1_sysclk2),
         CLK(NULL,               "pll1_sysclk3", &pll1_sysclk3),
+        CLK(NULL,               "async3",       &async3_clk),
         CLK("i2c_davinci.1",    NULL,           &i2c0_clk),
         CLK(NULL,               "timer0",       &timerp64_0_clk),
         CLK("davinci-wdt",      NULL,           &timerp64_1_clk),
@@ -909,30 +927,6 @@ static struct davinci_timer_info da850_timer_info = {
         .clocksource_id = T0_TOP,
 };
 
-static void da850_set_async3_src(int pllnum)
-{
-        struct clk *clk, *newparent = pllnum ? &pll1_sysclk2 : &pll0_sysclk2;
-        struct clk_lookup *c;
-        unsigned int v;
-        int ret;
-
-        for (c = da850_clks; c->clk; c++) {
-                clk = c->clk;
-                if (clk->flags & DA850_CLK_ASYNC3) {
-                        ret = clk_set_parent(clk, newparent);
-                        WARN(ret, "DA850: unable to re-parent clock %s",
-                                                                clk->name);
-                }
-       }
-
-        v = __raw_readl(DA8XX_SYSCFG0_VIRT(DA8XX_CFGCHIP3_REG));
-        if (pllnum)
-                v |= CFGCHIP3_ASYNC3_CLKSRC;
-        else
-                v &= ~CFGCHIP3_ASYNC3_CLKSRC;
-        __raw_writel(v, DA8XX_SYSCFG0_VIRT(DA8XX_CFGCHIP3_REG));
-}
-
 #ifdef CONFIG_CPU_FREQ
 /*
  * Notes:
@@ -1328,15 +1322,6 @@ void __init da850_init(void)
         if (WARN(!da8xx_syscfg1_base, "Unable to map syscfg1 module"))
                 return;
 
-        /*
-         * Move the clock source of Async3 domain to PLL1 SYSCLK2.
-         * This helps keeping the peripherals on this domain insulated
-         * from CPU frequency changes caused by DVFS. The firmware sets
-         * both PLL0 and PLL1 to the same frequency so, there should not
-         * be any noticeable change even in non-DVFS use cases.
-         */
-        da850_set_async3_src(1);
-
         /* Unlock writing to PLL0 registers */
         v = __raw_readl(DA8XX_SYSCFG0_VIRT(DA8XX_CFGCHIP0_REG));
         v &= ~CFGCHIP0_PLL_MASTER_LOCK;