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-rw-r--r--arch/sh/boards/overdrive/time.c119
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diff --git a/arch/sh/boards/overdrive/time.c b/arch/sh/boards/overdrive/time.c
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+/*
+ * arch/sh/boards/overdrive/time.c
+ *
+ * Copyright (C) 2000 Stuart Menefy (stuart.menefy@st.com)
+ * Copyright (C) 2002 Paul Mundt (lethal@chaoticdreams.org)
+ *
+ * May be copied or modified under the terms of the GNU General Public
+ * License. See linux/COPYING for more information.
+ *
+ * STMicroelectronics Overdrive Support.
+ */
+
+void od_time_init(void)
+{
+ struct frqcr_data {
+ unsigned short frqcr;
+ struct {
+ unsigned char multiplier;
+ unsigned char divisor;
+ } factor[3];
+ };
+
+ static struct frqcr_data st40_frqcr_table[] = {
+ { 0x000, {{1,1}, {1,1}, {1,2}}},
+ { 0x002, {{1,1}, {1,1}, {1,4}}},
+ { 0x004, {{1,1}, {1,1}, {1,8}}},
+ { 0x008, {{1,1}, {1,2}, {1,2}}},
+ { 0x00A, {{1,1}, {1,2}, {1,4}}},
+ { 0x00C, {{1,1}, {1,2}, {1,8}}},
+ { 0x011, {{1,1}, {2,3}, {1,6}}},
+ { 0x013, {{1,1}, {2,3}, {1,3}}},
+ { 0x01A, {{1,1}, {1,2}, {1,4}}},
+ { 0x01C, {{1,1}, {1,2}, {1,8}}},
+ { 0x023, {{1,1}, {2,3}, {1,3}}},
+ { 0x02C, {{1,1}, {1,2}, {1,8}}},
+ { 0x048, {{1,2}, {1,2}, {1,4}}},
+ { 0x04A, {{1,2}, {1,2}, {1,6}}},
+ { 0x04C, {{1,2}, {1,2}, {1,8}}},
+ { 0x05A, {{1,2}, {1,3}, {1,6}}},
+ { 0x05C, {{1,2}, {1,3}, {1,6}}},
+ { 0x063, {{1,2}, {1,4}, {1,4}}},
+ { 0x06C, {{1,2}, {1,4}, {1,8}}},
+ { 0x091, {{1,3}, {1,3}, {1,6}}},
+ { 0x093, {{1,3}, {1,3}, {1,6}}},
+ { 0x0A3, {{1,3}, {1,6}, {1,6}}},
+ { 0x0DA, {{1,4}, {1,4}, {1,8}}},
+ { 0x0DC, {{1,4}, {1,4}, {1,8}}},
+ { 0x0EC, {{1,4}, {1,8}, {1,8}}},
+ { 0x123, {{1,4}, {1,4}, {1,8}}},
+ { 0x16C, {{1,4}, {1,8}, {1,8}}},
+ };
+
+ struct memclk_data {
+ unsigned char multiplier;
+ unsigned char divisor;
+ };
+ static struct memclk_data st40_memclk_table[8] = {
+ {1,1}, // 000
+ {1,2}, // 001
+ {1,3}, // 010
+ {2,3}, // 011
+ {1,4}, // 100
+ {1,6}, // 101
+ {1,8}, // 110
+ {1,8} // 111
+ };
+
+ unsigned long pvr;
+
+ /*
+ * This should probably be moved into the SH3 probing code, and then
+ * use the processor structure to determine which CPU we are running
+ * on.
+ */
+ pvr = ctrl_inl(CCN_PVR);
+ printk("PVR %08x\n", pvr);
+
+ if (((pvr >> CCN_PVR_CHIP_SHIFT) & CCN_PVR_CHIP_MASK) == CCN_PVR_CHIP_ST40STB1) {
+ /*
+ * Unfortunatly the STB1 FRQCR values are different from the
+ * 7750 ones.
+ */
+ struct frqcr_data *d;
+ int a;
+ unsigned long memclkcr;
+ struct memclk_data *e;
+
+ for (a=0; a<ARRAY_SIZE(st40_frqcr_table); a++) {
+ d = &st40_frqcr_table[a];
+ if (d->frqcr == (frqcr & 0x1ff))
+ break;
+ }
+ if (a == ARRAY_SIZE(st40_frqcr_table)) {
+ d = st40_frqcr_table;
+ printk("ERROR: Unrecognised FRQCR value, using default multipliers\n");
+ }
+
+ memclkcr = ctrl_inl(CLOCKGEN_MEMCLKCR);
+ e = &st40_memclk_table[memclkcr & MEMCLKCR_RATIO_MASK];
+
+ printk("Clock multipliers: CPU: %d/%d Bus: %d/%d Mem: %d/%d Periph: %d/%d\n",
+ d->factor[0].multiplier, d->factor[0].divisor,
+ d->factor[1].multiplier, d->factor[1].divisor,
+ e->multiplier, e->divisor,
+ d->factor[2].multiplier, d->factor[2].divisor);
+
+ current_cpu_data.master_clock = current_cpu_data.module_clock *
+ d->factor[2].divisor /
+ d->factor[2].multiplier;
+ current_cpu_data.bus_clock = current_cpu_data.master_clock *
+ d->factor[1].multiplier /
+ d->factor[1].divisor;
+ current_cpu_data.memory_clock = current_cpu_data.master_clock *
+ e->multiplier / e->divisor;
+ current_cpu_data.cpu_clock = current_cpu_data.master_clock *
+ d->factor[0].multiplier /
+ d->factor[0].divisor;
+}
+