diff options
Diffstat (limited to 'arch/mips/vr41xx/common/bcu.c')
| -rw-r--r-- | arch/mips/vr41xx/common/bcu.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/arch/mips/vr41xx/common/bcu.c b/arch/mips/vr41xx/common/bcu.c new file mode 100644 index 000000000..0677d1779 --- /dev/null +++ b/arch/mips/vr41xx/common/bcu.c @@ -0,0 +1,210 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * bcu.c, Bus Control Unit routines for the NEC VR4100 series. + * + * Copyright (C) 2002 MontaVista Software Inc. + * Author: Yoichi Yuasa <source@mvista.com> + * Copyright (C) 2003-2005 Yoichi Yuasa <yuasa@linux-mips.org> + */ +/* + * Changes: + * MontaVista Software Inc. <source@mvista.com> + * - New creation, NEC VR4122 and VR4131 are supported. + * - Added support for NEC VR4111 and VR4121. + * + * Yoichi Yuasa <yuasa@linux-mips.org> + * - Added support for NEC VR4133. + */ +#include <linux/export.h> +#include <linux/kernel.h> +#include <linux/smp.h> +#include <linux/types.h> + +#include <asm/cpu-type.h> +#include <asm/cpu.h> +#include <asm/io.h> + +#define CLKSPEEDREG_TYPE1 (void __iomem *)KSEG1ADDR(0x0b000014) +#define CLKSPEEDREG_TYPE2 (void __iomem *)KSEG1ADDR(0x0f000014) + #define CLKSP(x) ((x) & 0x001f) + #define CLKSP_VR4133(x) ((x) & 0x0007) + + #define DIV2B 0x8000 + #define DIV3B 0x4000 + #define DIV4B 0x2000 + + #define DIVT(x) (((x) & 0xf000) >> 12) + #define DIVVT(x) (((x) & 0x0f00) >> 8) + + #define TDIVMODE(x) (2 << (((x) & 0x1000) >> 12)) + #define VTDIVMODE(x) (((x) & 0x0700) >> 8) + +static unsigned long vr41xx_vtclock; +static unsigned long vr41xx_tclock; + +unsigned long vr41xx_get_vtclock_frequency(void) +{ + return vr41xx_vtclock; +} + +EXPORT_SYMBOL_GPL(vr41xx_get_vtclock_frequency); + +unsigned long vr41xx_get_tclock_frequency(void) +{ + return vr41xx_tclock; +} + +EXPORT_SYMBOL_GPL(vr41xx_get_tclock_frequency); + +static inline uint16_t read_clkspeed(void) +{ + switch (current_cpu_type()) { + case CPU_VR4111: + case CPU_VR4121: return readw(CLKSPEEDREG_TYPE1); + case CPU_VR4122: + case CPU_VR4131: + case CPU_VR4133: return readw(CLKSPEEDREG_TYPE2); + default: + printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n"); + break; + } + + return 0; +} + +static inline unsigned long calculate_pclock(uint16_t clkspeed) +{ + unsigned long pclock = 0; + + switch (current_cpu_type()) { + case CPU_VR4111: + case CPU_VR4121: + pclock = 18432000 * 64; + pclock /= CLKSP(clkspeed); + break; + case CPU_VR4122: + pclock = 18432000 * 98; + pclock /= CLKSP(clkspeed); + break; + case CPU_VR4131: + pclock = 18432000 * 108; + pclock /= CLKSP(clkspeed); + break; + case CPU_VR4133: + switch (CLKSP_VR4133(clkspeed)) { + case 0: + pclock = 133000000; + break; + case 1: + pclock = 149000000; + break; + case 2: + pclock = 165900000; + break; + case 3: + pclock = 199100000; + break; + case 4: + pclock = 265900000; + break; + default: + printk(KERN_INFO "Unknown PClock speed for NEC VR4133\n"); + break; + } + break; + default: + printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n"); + break; + } + + printk(KERN_INFO "PClock: %ldHz\n", pclock); + + return pclock; +} + +static inline unsigned long calculate_vtclock(uint16_t clkspeed, unsigned long pclock) +{ + unsigned long vtclock = 0; + + switch (current_cpu_type()) { + case CPU_VR4111: + /* The NEC VR4111 doesn't have the VTClock. */ + break; + case CPU_VR4121: + vtclock = pclock; + /* DIVVT == 9 Divide by 1.5 . VTClock = (PClock * 6) / 9 */ + if (DIVVT(clkspeed) == 9) + vtclock = pclock * 6; + /* DIVVT == 10 Divide by 2.5 . VTClock = (PClock * 4) / 10 */ + else if (DIVVT(clkspeed) == 10) + vtclock = pclock * 4; + vtclock /= DIVVT(clkspeed); + printk(KERN_INFO "VTClock: %ldHz\n", vtclock); + break; + case CPU_VR4122: + if(VTDIVMODE(clkspeed) == 7) + vtclock = pclock / 1; + else if(VTDIVMODE(clkspeed) == 1) + vtclock = pclock / 2; + else + vtclock = pclock / VTDIVMODE(clkspeed); + printk(KERN_INFO "VTClock: %ldHz\n", vtclock); + break; + case CPU_VR4131: + case CPU_VR4133: + vtclock = pclock / VTDIVMODE(clkspeed); + printk(KERN_INFO "VTClock: %ldHz\n", vtclock); + break; + default: + printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n"); + break; + } + + return vtclock; +} + +static inline unsigned long calculate_tclock(uint16_t clkspeed, unsigned long pclock, + unsigned long vtclock) +{ + unsigned long tclock = 0; + + switch (current_cpu_type()) { + case CPU_VR4111: + if (!(clkspeed & DIV2B)) + tclock = pclock / 2; + else if (!(clkspeed & DIV3B)) + tclock = pclock / 3; + else if (!(clkspeed & DIV4B)) + tclock = pclock / 4; + break; + case CPU_VR4121: + tclock = pclock / DIVT(clkspeed); + break; + case CPU_VR4122: + case CPU_VR4131: + case CPU_VR4133: + tclock = vtclock / TDIVMODE(clkspeed); + break; + default: + printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n"); + break; + } + + printk(KERN_INFO "TClock: %ldHz\n", tclock); + + return tclock; +} + +void vr41xx_calculate_clock_frequency(void) +{ + unsigned long pclock; + uint16_t clkspeed; + + clkspeed = read_clkspeed(); + + pclock = calculate_pclock(clkspeed); + vr41xx_vtclock = calculate_vtclock(clkspeed, pclock); + vr41xx_tclock = calculate_tclock(clkspeed, pclock, vr41xx_vtclock); +} + +EXPORT_SYMBOL_GPL(vr41xx_calculate_clock_frequency); |