diff options
Diffstat (limited to 'arch/arm/mach-davinci/da850.c')
-rw-r--r-- | arch/arm/mach-davinci/da850.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/arch/arm/mach-davinci/da850.c b/arch/arm/mach-davinci/da850.c index f5c3a6a7131..575e9ccbb25 100644 --- a/arch/arm/mach-davinci/da850.c +++ b/arch/arm/mach-davinci/da850.c @@ -30,12 +30,17 @@ #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 #define DA850_REF_FREQ 24000000 +#define CFGCHIP3_ASYNC3_CLKSRC BIT(4) + static struct pll_data pll0_data = { .num = 1, .phys_base = DA8XX_PLL0_BASE, @@ -232,6 +237,7 @@ static struct clk uart1_clk = { .name = "uart1", .parent = &pll0_sysclk2, .lpsc = DA8XX_LPSC1_UART1, + .flags = DA850_CLK_ASYNC3, .psc_ctlr = 1, }; @@ -239,6 +245,7 @@ static struct clk uart2_clk = { .name = "uart2", .parent = &pll0_sysclk2, .lpsc = DA8XX_LPSC1_UART2, + .flags = DA850_CLK_ASYNC3, .psc_ctlr = 1, }; @@ -790,6 +797,30 @@ 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 davinci_clk *c; + unsigned int v; + int ret; + + for (c = da850_clks; c->lk.clk; c++) { + clk = c->lk.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_SYSCFG_VIRT(DA8XX_CFGCHIP3_REG)); + if (pllnum) + v |= CFGCHIP3_ASYNC3_CLKSRC; + else + v &= ~CFGCHIP3_ASYNC3_CLKSRC; + __raw_writel(v, DA8XX_SYSCFG_VIRT(DA8XX_CFGCHIP3_REG)); +} + static struct davinci_soc_info davinci_soc_info_da850 = { .io_desc = da850_io_desc, .io_desc_num = ARRAY_SIZE(da850_io_desc), @@ -823,4 +854,13 @@ void __init da850_init(void) davinci_soc_info_da850.pinmux_base = DA8XX_SYSCFG_VIRT(0x120); davinci_common_init(&davinci_soc_info_da850); + + /* + * 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 noticible change even in non-DVFS use cases. + */ + da850_set_async3_src(1); } |