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path: root/drivers/clk/pxa/clk-pxa25x.c
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Diffstat (limited to 'drivers/clk/pxa/clk-pxa25x.c')
-rw-r--r--drivers/clk/pxa/clk-pxa25x.c114
1 files changed, 103 insertions, 11 deletions
diff --git a/drivers/clk/pxa/clk-pxa25x.c b/drivers/clk/pxa/clk-pxa25x.c
index 56b0a6027e38..6416c1f8e632 100644
--- a/drivers/clk/pxa/clk-pxa25x.c
+++ b/drivers/clk/pxa/clk-pxa25x.c
@@ -18,6 +18,7 @@
#include <linux/io.h>
#include <linux/of.h>
#include <mach/pxa2xx-regs.h>
+#include <mach/smemc.h>
#include <dt-bindings/clock/pxa-clock.h>
#include "clk-pxa.h"
@@ -30,6 +31,17 @@ enum {
PXA_CORE_TURBO,
};
+#define PXA25x_CLKCFG(T) \
+ (CLKCFG_FCS | \
+ ((T) ? CLKCFG_TURBO : 0))
+#define PXA25x_CCCR(N2, M, L) (N2 << 7 | M << 5 | L)
+
+#define MDCNFG_DRAC2(mdcnfg) (((mdcnfg) >> 21) & 0x3)
+#define MDCNFG_DRAC0(mdcnfg) (((mdcnfg) >> 5) & 0x3)
+
+/* Define the refresh period in mSec for the SDRAM and the number of rows */
+#define SDRAM_TREF 64 /* standard 64ms SDRAM */
+
/*
* Various clock factors driven by the CCCR register.
*/
@@ -48,6 +60,34 @@ static const char * const get_freq_khz[] = {
"core", "run", "cpll", "memory"
};
+static int get_sdram_rows(void)
+{
+ static int sdram_rows;
+ unsigned int drac2 = 0, drac0 = 0;
+ u32 mdcnfg;
+
+ if (sdram_rows)
+ return sdram_rows;
+
+ mdcnfg = readl_relaxed(MDCNFG);
+
+ if (mdcnfg & (MDCNFG_DE2 | MDCNFG_DE3))
+ drac2 = MDCNFG_DRAC2(mdcnfg);
+
+ if (mdcnfg & (MDCNFG_DE0 | MDCNFG_DE1))
+ drac0 = MDCNFG_DRAC0(mdcnfg);
+
+ sdram_rows = 1 << (11 + max(drac0, drac2));
+ return sdram_rows;
+}
+
+static u32 mdrefr_dri(unsigned int freq_khz)
+{
+ u32 interval = freq_khz * SDRAM_TREF / get_sdram_rows();
+
+ return interval / 32;
+}
+
/*
* Get the clock frequency as reflected by CCCR and the turbo flag.
* We assume these values have been applied via a fcs.
@@ -139,6 +179,21 @@ static struct desc_clk_cken pxa25x_clocks[] __initdata = {
clk_pxa25x_memory_parents, 0),
};
+/*
+ * In this table, PXA25x_CCCR(N2, M, L) has the following meaning, where :
+ * - freq_cpll = n * m * L * 3.6864 MHz
+ * - n = N2 / 2
+ * - m = 2^(M - 1), where 1 <= M <= 3
+ * - l = L_clk_mult[L], ie. { 0, 27, 32, 36, 40, 45, 0, }[L]
+ */
+static struct pxa2xx_freq pxa25x_freqs[] = {
+ /* CPU MEMBUS CCCR DIV2 CCLKCFG */
+ { 99532800, 99500, PXA25x_CCCR(2, 1, 1), 1, PXA25x_CLKCFG(1)},
+ {199065600, 99500, PXA25x_CCCR(4, 1, 1), 0, PXA25x_CLKCFG(1)},
+ {298598400, 99500, PXA25x_CCCR(3, 2, 1), 0, PXA25x_CLKCFG(1)},
+ {398131200, 99500, PXA25x_CCCR(4, 2, 1), 0, PXA25x_CLKCFG(1)},
+};
+
static u8 clk_pxa25x_core_get_parent(struct clk_hw *hw)
{
unsigned long clkcfg;
@@ -151,13 +206,24 @@ static u8 clk_pxa25x_core_get_parent(struct clk_hw *hw)
return PXA_CORE_RUN;
}
-static unsigned long clk_pxa25x_core_get_rate(struct clk_hw *hw,
- unsigned long parent_rate)
+static int clk_pxa25x_core_set_parent(struct clk_hw *hw, u8 index)
{
- return parent_rate;
+ if (index > PXA_CORE_TURBO)
+ return -EINVAL;
+
+ pxa2xx_core_turbo_switch(index == PXA_CORE_TURBO);
+
+ return 0;
+}
+
+static int clk_pxa25x_core_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ return __clk_mux_determine_rate(hw, req);
}
+
PARENTS(clk_pxa25x_core) = { "run", "cpll" };
-MUX_RO_RATE_RO_OPS(clk_pxa25x_core, "core");
+MUX_OPS(clk_pxa25x_core, "core", CLK_SET_RATE_PARENT);
static unsigned long clk_pxa25x_run_get_rate(struct clk_hw *hw,
unsigned long parent_rate)
@@ -182,17 +248,42 @@ static unsigned long clk_pxa25x_cpll_get_rate(struct clk_hw *hw,
m = M_clk_mult[(cccr >> 5) & 0x03];
n2 = N2_clk_mult[(cccr >> 7) & 0x07];
- if (t)
- return m * l * n2 * parent_rate / 2;
- return m * l * parent_rate;
+ return m * l * n2 * parent_rate / 2;
+}
+
+static int clk_pxa25x_cpll_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ return pxa2xx_determine_rate(req, pxa25x_freqs,
+ ARRAY_SIZE(pxa25x_freqs));
+}
+
+static int clk_pxa25x_cpll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ int i;
+
+ pr_debug("%s(rate=%lu parent_rate=%lu)\n", __func__, rate, parent_rate);
+ for (i = 0; i < ARRAY_SIZE(pxa25x_freqs); i++)
+ if (pxa25x_freqs[i].cpll == rate)
+ break;
+
+ if (i >= ARRAY_SIZE(pxa25x_freqs))
+ return -EINVAL;
+
+ pxa2xx_cpll_change(&pxa25x_freqs[i], mdrefr_dri, MDREFR, CCCR);
+
+ return 0;
}
PARENTS(clk_pxa25x_cpll) = { "osc_3_6864mhz" };
-RATE_RO_OPS(clk_pxa25x_cpll, "cpll");
+RATE_OPS(clk_pxa25x_cpll, "cpll");
static void __init pxa25x_register_core(void)
{
- clk_register_clk_pxa25x_cpll();
- clk_register_clk_pxa25x_run();
+ clkdev_pxa_register(CLK_NONE, "cpll", NULL,
+ clk_register_clk_pxa25x_cpll());
+ clkdev_pxa_register(CLK_NONE, "run", NULL,
+ clk_register_clk_pxa25x_run());
clkdev_pxa_register(CLK_CORE, "core", NULL,
clk_register_clk_pxa25x_core());
}
@@ -214,7 +305,8 @@ static void __init pxa25x_base_clocks_init(void)
{
pxa25x_register_plls();
pxa25x_register_core();
- clk_register_clk_pxa25x_memory();
+ clkdev_pxa_register(CLK_NONE, "system_bus", NULL,
+ clk_register_clk_pxa25x_memory());
}
#define DUMMY_CLK(_con_id, _dev_id, _parent) \