diff options
Diffstat (limited to 'arch/arm/mach-ep93xx')
| -rw-r--r-- | arch/arm/mach-ep93xx/clock.c | 69 | ||||
| -rw-r--r-- | arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h | 5 |
2 files changed, 65 insertions, 9 deletions
diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c index e8ebeaea6c4..b2eede5531c 100644 --- a/arch/arm/mach-ep93xx/clock.c +++ b/arch/arm/mach-ep93xx/clock.c @@ -21,15 +21,50 @@ #include <asm/div64.h> #include <mach/hardware.h> + +/* + * The EP93xx has two external crystal oscillators. To generate the + * required high-frequency clocks, the processor uses two phase-locked- + * loops (PLLs) to multiply the incoming external clock signal to much + * higher frequencies that are then divided down by programmable dividers + * to produce the needed clocks. The PLLs operate independently of one + * another. + */ +#define EP93XX_EXT_CLK_RATE 14745600 +#define EP93XX_EXT_RTC_RATE 32768 + + struct clk { unsigned long rate; int users; + int sw_locked; u32 enable_reg; u32 enable_mask; + + unsigned long (*get_rate)(struct clk *clk); }; -static struct clk clk_uart = { - .rate = 14745600, + +static unsigned long get_uart_rate(struct clk *clk); + + +static struct clk clk_uart1 = { + .sw_locked = 1, + .enable_reg = EP93XX_SYSCON_DEVICE_CONFIG, + .enable_mask = EP93XX_SYSCON_DEVICE_CONFIG_U1EN, + .get_rate = get_uart_rate, +}; +static struct clk clk_uart2 = { + .sw_locked = 1, + .enable_reg = EP93XX_SYSCON_DEVICE_CONFIG, + .enable_mask = EP93XX_SYSCON_DEVICE_CONFIG_U2EN, + .get_rate = get_uart_rate, +}; +static struct clk clk_uart3 = { + .sw_locked = 1, + .enable_reg = EP93XX_SYSCON_DEVICE_CONFIG, + .enable_mask = EP93XX_SYSCON_DEVICE_CONFIG_U3EN, + .get_rate = get_uart_rate, }; static struct clk clk_pll1; static struct clk clk_f; @@ -95,9 +130,9 @@ static struct clk clk_m2m1 = { { .dev_id = dev, .con_id = con, .clk = ck } static struct clk_lookup clocks[] = { - INIT_CK("apb:uart1", NULL, &clk_uart), - INIT_CK("apb:uart2", NULL, &clk_uart), - INIT_CK("apb:uart3", NULL, &clk_uart), + INIT_CK("apb:uart1", NULL, &clk_uart1), + INIT_CK("apb:uart2", NULL, &clk_uart2), + INIT_CK("apb:uart3", NULL, &clk_uart3), INIT_CK(NULL, "pll1", &clk_pll1), INIT_CK(NULL, "fclk", &clk_f), INIT_CK(NULL, "hclk", &clk_h), @@ -125,6 +160,8 @@ int clk_enable(struct clk *clk) u32 value; value = __raw_readl(clk->enable_reg); + if (clk->sw_locked) + __raw_writel(0xaa, EP93XX_SYSCON_SWLOCK); __raw_writel(value | clk->enable_mask, clk->enable_reg); } @@ -138,13 +175,29 @@ void clk_disable(struct clk *clk) u32 value; value = __raw_readl(clk->enable_reg); + if (clk->sw_locked) + __raw_writel(0xaa, EP93XX_SYSCON_SWLOCK); __raw_writel(value & ~clk->enable_mask, clk->enable_reg); } } EXPORT_SYMBOL(clk_disable); +static unsigned long get_uart_rate(struct clk *clk) +{ + u32 value; + + value = __raw_readl(EP93XX_SYSCON_CLOCK_CONTROL); + if (value & EP93XX_SYSCON_CLOCK_UARTBAUD) + return EP93XX_EXT_CLK_RATE; + else + return EP93XX_EXT_CLK_RATE / 2; +} + unsigned long clk_get_rate(struct clk *clk) { + if (clk->get_rate) + return clk->get_rate(clk); + return clk->rate; } EXPORT_SYMBOL(clk_get_rate); @@ -162,7 +215,7 @@ static unsigned long calc_pll_rate(u32 config_word) unsigned long long rate; int i; - rate = 14745600; + rate = EP93XX_EXT_CLK_RATE; rate *= ((config_word >> 11) & 0x1f) + 1; /* X1FBD */ rate *= ((config_word >> 5) & 0x3f) + 1; /* X2FBD */ do_div(rate, (config_word & 0x1f) + 1); /* X2IPD */ @@ -195,7 +248,7 @@ static int __init ep93xx_clock_init(void) value = __raw_readl(EP93XX_SYSCON_CLOCK_SET1); if (!(value & 0x00800000)) { /* PLL1 bypassed? */ - clk_pll1.rate = 14745600; + clk_pll1.rate = EP93XX_EXT_CLK_RATE; } else { clk_pll1.rate = calc_pll_rate(value); } @@ -206,7 +259,7 @@ static int __init ep93xx_clock_init(void) value = __raw_readl(EP93XX_SYSCON_CLOCK_SET2); if (!(value & 0x00080000)) { /* PLL2 bypassed? */ - clk_pll2.rate = 14745600; + clk_pll2.rate = EP93XX_EXT_CLK_RATE; } else if (value & 0x00040000) { /* PLL2 enabled? */ clk_pll2.rate = calc_pll_rate(value); } else { diff --git a/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h b/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h index f66be12b856..1732de7629a 100644 --- a/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h +++ b/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h @@ -159,7 +159,10 @@ #define EP93XX_SYSCON_CLOCK_SET1 EP93XX_SYSCON_REG(0x20) #define EP93XX_SYSCON_CLOCK_SET2 EP93XX_SYSCON_REG(0x24) #define EP93XX_SYSCON_DEVICE_CONFIG EP93XX_SYSCON_REG(0x80) -#define EP93XX_SYSCON_DEVICE_CONFIG_CRUNCH_ENABLE 0x00800000 +#define EP93XX_SYSCON_DEVICE_CONFIG_U3EN (1<<24) +#define EP93XX_SYSCON_DEVICE_CONFIG_CRUNCH_ENABLE (1<<23) +#define EP93XX_SYSCON_DEVICE_CONFIG_U2EN (1<<20) +#define EP93XX_SYSCON_DEVICE_CONFIG_U1EN (1<<18) #define EP93XX_SYSCON_SWLOCK EP93XX_SYSCON_REG(0xc0) #define EP93XX_WATCHDOG_BASE (EP93XX_APB_VIRT_BASE + 0x00140000) |