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-rw-r--r--arch/arm/mach-ep93xx/clock.c69
1 files changed, 61 insertions, 8 deletions
diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c
index e8ebeaea6c48..b2eede5531c8 100644
--- a/arch/arm/mach-ep93xx/clock.c
+++ b/arch/arm/mach-ep93xx/clock.c
@@ -21,15 +21,50 @@
21#include <asm/div64.h> 21#include <asm/div64.h>
22#include <mach/hardware.h> 22#include <mach/hardware.h>
23 23
24
25/*
26 * The EP93xx has two external crystal oscillators. To generate the
27 * required high-frequency clocks, the processor uses two phase-locked-
28 * loops (PLLs) to multiply the incoming external clock signal to much
29 * higher frequencies that are then divided down by programmable dividers
30 * to produce the needed clocks. The PLLs operate independently of one
31 * another.
32 */
33#define EP93XX_EXT_CLK_RATE 14745600
34#define EP93XX_EXT_RTC_RATE 32768
35
36
24struct clk { 37struct clk {
25 unsigned long rate; 38 unsigned long rate;
26 int users; 39 int users;
40 int sw_locked;
27 u32 enable_reg; 41 u32 enable_reg;
28 u32 enable_mask; 42 u32 enable_mask;
43
44 unsigned long (*get_rate)(struct clk *clk);
29}; 45};
30 46
31static struct clk clk_uart = { 47
32 .rate = 14745600, 48static unsigned long get_uart_rate(struct clk *clk);
49
50
51static struct clk clk_uart1 = {
52 .sw_locked = 1,
53 .enable_reg = EP93XX_SYSCON_DEVICE_CONFIG,
54 .enable_mask = EP93XX_SYSCON_DEVICE_CONFIG_U1EN,
55 .get_rate = get_uart_rate,
56};
57static struct clk clk_uart2 = {
58 .sw_locked = 1,
59 .enable_reg = EP93XX_SYSCON_DEVICE_CONFIG,
60 .enable_mask = EP93XX_SYSCON_DEVICE_CONFIG_U2EN,
61 .get_rate = get_uart_rate,
62};
63static struct clk clk_uart3 = {
64 .sw_locked = 1,
65 .enable_reg = EP93XX_SYSCON_DEVICE_CONFIG,
66 .enable_mask = EP93XX_SYSCON_DEVICE_CONFIG_U3EN,
67 .get_rate = get_uart_rate,
33}; 68};
34static struct clk clk_pll1; 69static struct clk clk_pll1;
35static struct clk clk_f; 70static struct clk clk_f;
@@ -95,9 +130,9 @@ static struct clk clk_m2m1 = {
95 { .dev_id = dev, .con_id = con, .clk = ck } 130 { .dev_id = dev, .con_id = con, .clk = ck }
96 131
97static struct clk_lookup clocks[] = { 132static struct clk_lookup clocks[] = {
98 INIT_CK("apb:uart1", NULL, &clk_uart), 133 INIT_CK("apb:uart1", NULL, &clk_uart1),
99 INIT_CK("apb:uart2", NULL, &clk_uart), 134 INIT_CK("apb:uart2", NULL, &clk_uart2),
100 INIT_CK("apb:uart3", NULL, &clk_uart), 135 INIT_CK("apb:uart3", NULL, &clk_uart3),
101 INIT_CK(NULL, "pll1", &clk_pll1), 136 INIT_CK(NULL, "pll1", &clk_pll1),
102 INIT_CK(NULL, "fclk", &clk_f), 137 INIT_CK(NULL, "fclk", &clk_f),
103 INIT_CK(NULL, "hclk", &clk_h), 138 INIT_CK(NULL, "hclk", &clk_h),
@@ -125,6 +160,8 @@ int clk_enable(struct clk *clk)
125 u32 value; 160 u32 value;
126 161
127 value = __raw_readl(clk->enable_reg); 162 value = __raw_readl(clk->enable_reg);
163 if (clk->sw_locked)
164 __raw_writel(0xaa, EP93XX_SYSCON_SWLOCK);
128 __raw_writel(value | clk->enable_mask, clk->enable_reg); 165 __raw_writel(value | clk->enable_mask, clk->enable_reg);
129 } 166 }
130 167
@@ -138,13 +175,29 @@ void clk_disable(struct clk *clk)
138 u32 value; 175 u32 value;
139 176
140 value = __raw_readl(clk->enable_reg); 177 value = __raw_readl(clk->enable_reg);
178 if (clk->sw_locked)
179 __raw_writel(0xaa, EP93XX_SYSCON_SWLOCK);
141 __raw_writel(value & ~clk->enable_mask, clk->enable_reg); 180 __raw_writel(value & ~clk->enable_mask, clk->enable_reg);
142 } 181 }
143} 182}
144EXPORT_SYMBOL(clk_disable); 183EXPORT_SYMBOL(clk_disable);
145 184
185static unsigned long get_uart_rate(struct clk *clk)
186{
187 u32 value;
188
189 value = __raw_readl(EP93XX_SYSCON_CLOCK_CONTROL);
190 if (value & EP93XX_SYSCON_CLOCK_UARTBAUD)
191 return EP93XX_EXT_CLK_RATE;
192 else
193 return EP93XX_EXT_CLK_RATE / 2;
194}
195
146unsigned long clk_get_rate(struct clk *clk) 196unsigned long clk_get_rate(struct clk *clk)
147{ 197{
198 if (clk->get_rate)
199 return clk->get_rate(clk);
200
148 return clk->rate; 201 return clk->rate;
149} 202}
150EXPORT_SYMBOL(clk_get_rate); 203EXPORT_SYMBOL(clk_get_rate);
@@ -162,7 +215,7 @@ static unsigned long calc_pll_rate(u32 config_word)
162 unsigned long long rate; 215 unsigned long long rate;
163 int i; 216 int i;
164 217
165 rate = 14745600; 218 rate = EP93XX_EXT_CLK_RATE;
166 rate *= ((config_word >> 11) & 0x1f) + 1; /* X1FBD */ 219 rate *= ((config_word >> 11) & 0x1f) + 1; /* X1FBD */
167 rate *= ((config_word >> 5) & 0x3f) + 1; /* X2FBD */ 220 rate *= ((config_word >> 5) & 0x3f) + 1; /* X2FBD */
168 do_div(rate, (config_word & 0x1f) + 1); /* X2IPD */ 221 do_div(rate, (config_word & 0x1f) + 1); /* X2IPD */
@@ -195,7 +248,7 @@ static int __init ep93xx_clock_init(void)
195 248
196 value = __raw_readl(EP93XX_SYSCON_CLOCK_SET1); 249 value = __raw_readl(EP93XX_SYSCON_CLOCK_SET1);
197 if (!(value & 0x00800000)) { /* PLL1 bypassed? */ 250 if (!(value & 0x00800000)) { /* PLL1 bypassed? */
198 clk_pll1.rate = 14745600; 251 clk_pll1.rate = EP93XX_EXT_CLK_RATE;
199 } else { 252 } else {
200 clk_pll1.rate = calc_pll_rate(value); 253 clk_pll1.rate = calc_pll_rate(value);
201 } 254 }
@@ -206,7 +259,7 @@ static int __init ep93xx_clock_init(void)
206 259
207 value = __raw_readl(EP93XX_SYSCON_CLOCK_SET2); 260 value = __raw_readl(EP93XX_SYSCON_CLOCK_SET2);
208 if (!(value & 0x00080000)) { /* PLL2 bypassed? */ 261 if (!(value & 0x00080000)) { /* PLL2 bypassed? */
209 clk_pll2.rate = 14745600; 262 clk_pll2.rate = EP93XX_EXT_CLK_RATE;
210 } else if (value & 0x00040000) { /* PLL2 enabled? */ 263 } else if (value & 0x00040000) { /* PLL2 enabled? */
211 clk_pll2.rate = calc_pll_rate(value); 264 clk_pll2.rate = calc_pll_rate(value);
212 } else { 265 } else {