patch-2.4.20 linux-2.4.20/arch/mips/kernel/cpu-probe.c
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- Lines: 490
- Date:
Thu Nov 28 15:53:10 2002
- Orig file:
linux-2.4.19/arch/mips/kernel/cpu-probe.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -urN linux-2.4.19/arch/mips/kernel/cpu-probe.c linux-2.4.20/arch/mips/kernel/cpu-probe.c
@@ -0,0 +1,489 @@
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/stddef.h>
+#include <asm/bugs.h>
+#include <asm/cpu.h>
+#include <asm/mipsregs.h>
+
+/*
+ * Not all of the MIPS CPUs have the "wait" instruction available. Moreover,
+ * the implementation of the "wait" feature differs between CPU families. This
+ * points to the function that implements CPU specific wait.
+ * The wait instruction stops the pipeline and reduces the power consumption of
+ * the CPU very much.
+ */
+void (*cpu_wait)(void) = NULL;
+
+static void r3081_wait(void)
+{
+ unsigned long cfg = read_32bit_cp0_register(CP0_CONF);
+ write_32bit_cp0_register(CP0_CONF, cfg|CONF_HALT);
+}
+
+static void r39xx_wait(void)
+{
+ unsigned long cfg = read_32bit_cp0_register(CP0_CONF);
+ write_32bit_cp0_register(CP0_CONF, cfg|TX39_CONF_HALT);
+}
+
+static void r4k_wait(void)
+{
+ __asm__(".set\tmips3\n\t"
+ "wait\n\t"
+ ".set\tmips0");
+}
+
+void au1k_wait(void)
+{
+#ifdef CONFIG_PM
+ /* using the wait instruction makes CP0 counter unusable */
+ __asm__(".set\tmips3\n\t"
+ "wait\n\t"
+ "nop\n\t" "nop\n\t" "nop\n\t" "nop\n\t" ".set\tmips0");
+#else
+ __asm__("nop\n\t" "nop\n\t");
+#endif
+}
+
+static inline void check_wait(void)
+{
+ printk("Checking for 'wait' instruction... ");
+ switch(mips_cpu.cputype) {
+ case CPU_R3081:
+ case CPU_R3081E:
+ cpu_wait = r3081_wait;
+ printk(" available.\n");
+ break;
+ case CPU_TX3927:
+ case CPU_TX39XX:
+ cpu_wait = r39xx_wait;
+ printk(" available.\n");
+ break;
+ case CPU_R4200:
+/* case CPU_R4300: */
+ case CPU_R4600:
+ case CPU_R4640:
+ case CPU_R4650:
+ case CPU_R4700:
+ case CPU_R5000:
+ case CPU_NEVADA:
+ case CPU_RM7000:
+ case CPU_TX49XX:
+ case CPU_4KC:
+ case CPU_4KEC:
+ case CPU_4KSC:
+ case CPU_5KC:
+/* case CPU_20KC:*/
+ cpu_wait = r4k_wait;
+ printk(" available.\n");
+ break;
+ case CPU_AU1000:
+ case CPU_AU1100:
+ case CPU_AU1500:
+ cpu_wait = au1k_wait;
+ printk(" available.\n");
+ break;
+ default:
+ printk(" unavailable.\n");
+ break;
+ }
+}
+
+void __init check_bugs(void)
+{
+ check_wait();
+}
+
+/*
+ * Probe whether cpu has config register by trying to play with
+ * alternate cache bit and see whether it matters.
+ * It's used by cpu_probe to distinguish between R3000A and R3081.
+ */
+static inline int cpu_has_confreg(void)
+{
+#ifdef CONFIG_CPU_R3000
+ extern unsigned long r3k_cache_size(unsigned long);
+ unsigned long size1, size2;
+ unsigned long cfg = read_32bit_cp0_register(CP0_CONF);
+
+ size1 = r3k_cache_size(ST0_ISC);
+ write_32bit_cp0_register(CP0_CONF, cfg^CONF_AC);
+ size2 = r3k_cache_size(ST0_ISC);
+ write_32bit_cp0_register(CP0_CONF, cfg);
+ return size1 != size2;
+#else
+ return 0;
+#endif
+}
+
+/*
+ * Get the FPU Implementation/Revision.
+ */
+static inline unsigned long cpu_get_fpu_id(void)
+{
+ unsigned long tmp, fpu_id;
+
+ tmp = read_32bit_cp0_register(CP0_STATUS);
+ __enable_fpu();
+ fpu_id = read_32bit_cp1_register(CP1_REVISION);
+ write_32bit_cp0_register(CP0_STATUS, tmp);
+ return fpu_id;
+}
+
+/*
+ * Check the CPU has an FPU the official way.
+ */
+static inline int cpu_has_fpu(void)
+{
+ return ((cpu_get_fpu_id() & 0xff00) != FPIR_IMP_NONE);
+}
+
+/* declaration of the global struct */
+struct mips_cpu mips_cpu = {
+ processor_id: PRID_IMP_UNKNOWN,
+ fpu_id: FPIR_IMP_NONE,
+ cputype: CPU_UNKNOWN
+};
+
+/* Shortcut for assembler access to mips_cpu.options */
+int *cpuoptions = &mips_cpu.options;
+
+#define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4KTLB \
+ | MIPS_CPU_COUNTER | MIPS_CPU_CACHE_CDEX)
+
+__init void cpu_probe(void)
+{
+#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
+ unsigned long config0 = read_32bit_cp0_register(CP0_CONFIG);
+ unsigned long config1;
+
+ if (config0 & (1 << 31)) {
+ /* MIPS32 or MIPS64 compliant CPU. Read Config 1 register. */
+ mips_cpu.options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
+ MIPS_CPU_4KTLB | MIPS_CPU_COUNTER | MIPS_CPU_DIVEC;
+ config1 = read_mips32_cp0_config1();
+ if (config1 & (1 << 3))
+ mips_cpu.options |= MIPS_CPU_WATCH;
+ if (config1 & (1 << 2))
+ mips_cpu.options |= MIPS_CPU_MIPS16;
+ if (config1 & (1 << 1))
+ mips_cpu.options |= MIPS_CPU_EJTAG;
+ if (config1 & 1) {
+ mips_cpu.options |= MIPS_CPU_FPU;
+#if defined(CONFIG_CPU_MIPS64)
+ mips_cpu.options |= MIPS_CPU_32FPR;
+#endif
+ }
+ mips_cpu.scache.flags = MIPS_CACHE_NOT_PRESENT;
+ }
+#endif
+ mips_cpu.processor_id = read_32bit_cp0_register(CP0_PRID);
+ switch (mips_cpu.processor_id & 0xff0000) {
+ case PRID_COMP_LEGACY:
+ switch (mips_cpu.processor_id & 0xff00) {
+ case PRID_IMP_R2000:
+ mips_cpu.cputype = CPU_R2000;
+ mips_cpu.isa_level = MIPS_CPU_ISA_I;
+ mips_cpu.options = MIPS_CPU_TLB | MIPS_CPU_NOFPUEX;
+ if (cpu_has_fpu())
+ mips_cpu.options |= MIPS_CPU_FPU;
+ mips_cpu.tlbsize = 64;
+ break;
+ case PRID_IMP_R3000:
+ if ((mips_cpu.processor_id & 0xff) == PRID_REV_R3000A)
+ if (cpu_has_confreg())
+ mips_cpu.cputype = CPU_R3081E;
+ else
+ mips_cpu.cputype = CPU_R3000A;
+ else
+ mips_cpu.cputype = CPU_R3000;
+ mips_cpu.isa_level = MIPS_CPU_ISA_I;
+ mips_cpu.options = MIPS_CPU_TLB | MIPS_CPU_NOFPUEX;
+ if (cpu_has_fpu())
+ mips_cpu.options |= MIPS_CPU_FPU;
+ mips_cpu.tlbsize = 64;
+ break;
+ case PRID_IMP_R4000:
+ if ((mips_cpu.processor_id & 0xff) == PRID_REV_R4400)
+ mips_cpu.cputype = CPU_R4400SC;
+ else
+ mips_cpu.cputype = CPU_R4000SC;
+ mips_cpu.isa_level = MIPS_CPU_ISA_III;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU |
+ MIPS_CPU_32FPR | MIPS_CPU_WATCH |
+ MIPS_CPU_VCE;
+ mips_cpu.tlbsize = 48;
+ break;
+ case PRID_IMP_VR41XX:
+ switch (mips_cpu.processor_id & 0xf0) {
+#ifndef CONFIG_VR4181
+ case PRID_REV_VR4111:
+ mips_cpu.cputype = CPU_VR4111;
+ break;
+#else
+ case PRID_REV_VR4181:
+ mips_cpu.cputype = CPU_VR4181;
+ break;
+#endif
+ case PRID_REV_VR4121:
+ mips_cpu.cputype = CPU_VR4121;
+ break;
+ case PRID_REV_VR4122:
+ if ((mips_cpu.processor_id & 0xf) < 0x3)
+ mips_cpu.cputype = CPU_VR4122;
+ else
+ mips_cpu.cputype = CPU_VR4181A;
+ break;
+ case PRID_REV_VR4131:
+ mips_cpu.cputype = CPU_VR4131;
+ mips_cpu.icache.ways = 2;
+ mips_cpu.dcache.ways = 2;
+ break;
+ default:
+ printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
+ mips_cpu.cputype = CPU_VR41XX;
+ break;
+ }
+ mips_cpu.isa_level = MIPS_CPU_ISA_III;
+ mips_cpu.options = R4K_OPTS;
+ mips_cpu.tlbsize = 32;
+ break;
+ case PRID_IMP_R4300:
+ mips_cpu.cputype = CPU_R4300;
+ mips_cpu.isa_level = MIPS_CPU_ISA_III;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU |
+ MIPS_CPU_32FPR;
+ mips_cpu.tlbsize = 32;
+ break;
+ case PRID_IMP_R4600:
+ mips_cpu.cputype = CPU_R4600;
+ mips_cpu.isa_level = MIPS_CPU_ISA_III;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU;
+ mips_cpu.tlbsize = 48;
+ break;
+ #if 0
+ case PRID_IMP_R4650:
+ /*
+ * This processor doesn't have an MMU, so it's not
+ * "real easy" to run Linux on it. It is left purely
+ * for documentation. Commented out because it shares
+ * it's c0_prid id number with the TX3900.
+ */
+ mips_cpu.cputype = CPU_R4650;
+ mips_cpu.isa_level = MIPS_CPU_ISA_III;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU;
+ mips_cpu.tlbsize = 48;
+ break;
+ #endif
+ case PRID_IMP_TX39:
+ mips_cpu.isa_level = MIPS_CPU_ISA_I;
+ mips_cpu.options = MIPS_CPU_TLB;
+
+ if ((mips_cpu.processor_id & 0xf0) ==
+ (PRID_REV_TX3927 & 0xf0)) {
+ mips_cpu.cputype = CPU_TX3927;
+ mips_cpu.tlbsize = 64;
+ mips_cpu.icache.ways = 2;
+ mips_cpu.dcache.ways = 2;
+ } else {
+ switch (mips_cpu.processor_id & 0xff) {
+ case PRID_REV_TX3912:
+ mips_cpu.cputype = CPU_TX3912;
+ mips_cpu.tlbsize = 32;
+ break;
+ case PRID_REV_TX3922:
+ mips_cpu.cputype = CPU_TX3922;
+ mips_cpu.tlbsize = 64;
+ break;
+ default:
+ mips_cpu.cputype = CPU_UNKNOWN;
+ break;
+ }
+ }
+ break;
+ case PRID_IMP_R4700:
+ mips_cpu.cputype = CPU_R4700;
+ mips_cpu.isa_level = MIPS_CPU_ISA_III;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU |
+ MIPS_CPU_32FPR;
+ mips_cpu.tlbsize = 48;
+ break;
+ case PRID_IMP_TX49:
+ mips_cpu.cputype = CPU_TX49XX;
+ mips_cpu.isa_level = MIPS_CPU_ISA_III;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU |
+ MIPS_CPU_32FPR;
+ mips_cpu.tlbsize = 48;
+ mips_cpu.icache.ways = 4;
+ mips_cpu.dcache.ways = 4;
+ break;
+ case PRID_IMP_R5000:
+ mips_cpu.cputype = CPU_R5000;
+ mips_cpu.isa_level = MIPS_CPU_ISA_IV;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU |
+ MIPS_CPU_32FPR;
+ mips_cpu.tlbsize = 48;
+ break;
+ case PRID_IMP_R5432:
+ mips_cpu.cputype = CPU_R5432;
+ mips_cpu.isa_level = MIPS_CPU_ISA_IV;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU |
+ MIPS_CPU_32FPR | MIPS_CPU_WATCH;
+ mips_cpu.tlbsize = 48;
+ break;
+ case PRID_IMP_R5500:
+ mips_cpu.cputype = CPU_R5500;
+ mips_cpu.isa_level = MIPS_CPU_ISA_IV;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU |
+ MIPS_CPU_32FPR | MIPS_CPU_WATCH;
+ mips_cpu.tlbsize = 48;
+ break;
+ case PRID_IMP_NEVADA:
+ mips_cpu.cputype = CPU_NEVADA;
+ mips_cpu.isa_level = MIPS_CPU_ISA_IV;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU |
+ MIPS_CPU_32FPR | MIPS_CPU_DIVEC;
+ mips_cpu.tlbsize = 48;
+ mips_cpu.icache.ways = 2;
+ mips_cpu.dcache.ways = 2;
+ break;
+ case PRID_IMP_R6000:
+ mips_cpu.cputype = CPU_R6000;
+ mips_cpu.isa_level = MIPS_CPU_ISA_II;
+ mips_cpu.options = MIPS_CPU_TLB | MIPS_CPU_FPU;
+ mips_cpu.tlbsize = 32;
+ break;
+ case PRID_IMP_R6000A:
+ mips_cpu.cputype = CPU_R6000A;
+ mips_cpu.isa_level = MIPS_CPU_ISA_II;
+ mips_cpu.options = MIPS_CPU_TLB | MIPS_CPU_FPU;
+ mips_cpu.tlbsize = 32;
+ break;
+ case PRID_IMP_RM7000:
+ mips_cpu.cputype = CPU_RM7000;
+ mips_cpu.isa_level = MIPS_CPU_ISA_IV;
+ mips_cpu.options = R4K_OPTS | MIPS_CPU_FPU |
+ MIPS_CPU_32FPR;
+ /*
+ * Undocumented RM7000: Bit 29 in the info register of
+ * the RM7000 v2.0 indicates if the TLB has 48 or 64
+ * entries.
+ *
+ * 29 1 => 64 entry JTLB
+ * 0 => 48 entry JTLB
+ */
+ mips_cpu.tlbsize = (get_info() & (1 << 29)) ? 64 : 48;
+ break;
+ case PRID_IMP_R8000:
+ mips_cpu.cputype = CPU_R8000;
+ mips_cpu.isa_level = MIPS_CPU_ISA_IV;
+ mips_cpu.options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
+ MIPS_CPU_FPU | MIPS_CPU_32FPR;
+ mips_cpu.tlbsize = 384; /* has weird TLB: 3-way x 128 */
+ break;
+ case PRID_IMP_R10000:
+ mips_cpu.cputype = CPU_R10000;
+ mips_cpu.isa_level = MIPS_CPU_ISA_IV;
+ mips_cpu.options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
+ MIPS_CPU_FPU | MIPS_CPU_32FPR |
+ MIPS_CPU_COUNTER | MIPS_CPU_WATCH;
+ mips_cpu.tlbsize = 64;
+ break;
+ case PRID_IMP_R12000:
+ mips_cpu.cputype = CPU_R12000;
+ mips_cpu.isa_level = MIPS_CPU_ISA_IV;
+ mips_cpu.options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
+ MIPS_CPU_FPU | MIPS_CPU_32FPR |
+ MIPS_CPU_COUNTER | MIPS_CPU_WATCH;
+ mips_cpu.tlbsize = 64;
+ break;
+ default:
+ mips_cpu.cputype = CPU_UNKNOWN;
+ break;
+ }
+ break;
+#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
+ case PRID_COMP_MIPS:
+ switch (mips_cpu.processor_id & 0xff00) {
+ case PRID_IMP_4KC:
+ mips_cpu.cputype = CPU_4KC;
+ mips_cpu.isa_level = MIPS_CPU_ISA_M32;
+ break;
+ case PRID_IMP_4KEC:
+ mips_cpu.cputype = CPU_4KEC;
+ mips_cpu.isa_level = MIPS_CPU_ISA_M32;
+ break;
+ case PRID_IMP_4KSC:
+ mips_cpu.cputype = CPU_4KSC;
+ mips_cpu.isa_level = MIPS_CPU_ISA_M32;
+ break;
+ case PRID_IMP_5KC:
+ mips_cpu.cputype = CPU_5KC;
+ mips_cpu.isa_level = MIPS_CPU_ISA_M64;
+ break;
+ case PRID_IMP_20KC:
+ mips_cpu.cputype = CPU_20KC;
+ mips_cpu.isa_level = MIPS_CPU_ISA_M64;
+ break;
+ default:
+ mips_cpu.cputype = CPU_UNKNOWN;
+ break;
+ }
+ break;
+ case PRID_COMP_ALCHEMY:
+ switch (mips_cpu.processor_id & 0xff00) {
+ case PRID_IMP_AU1_REV1:
+ case PRID_IMP_AU1_REV2:
+ switch ((mips_cpu.processor_id >> 24) & 0xff) {
+ case 0:
+ mips_cpu.cputype = CPU_AU1000;
+ break;
+ case 1:
+ mips_cpu.cputype = CPU_AU1500;
+ break;
+ case 2:
+ mips_cpu.cputype = CPU_AU1100;
+ break;
+ default:
+ panic("Unknown Au Core!");
+ break;
+ }
+ mips_cpu.isa_level = MIPS_CPU_ISA_M32;
+ break;
+ default:
+ mips_cpu.cputype = CPU_UNKNOWN;
+ break;
+ }
+ break;
+#endif /* CONFIG_CPU_MIPS32 */
+ case PRID_COMP_SIBYTE:
+ switch (mips_cpu.processor_id & 0xff00) {
+ case PRID_IMP_SB1:
+ mips_cpu.cputype = CPU_SB1;
+ mips_cpu.isa_level = MIPS_CPU_ISA_M64;
+ mips_cpu.options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
+ MIPS_CPU_COUNTER | MIPS_CPU_DIVEC |
+ MIPS_CPU_MCHECK;
+#ifndef CONFIG_SB1_PASS_1_WORKAROUNDS
+ /* FPU in pass1 is known to have issues. */
+ mips_cpu.options |= MIPS_CPU_FPU;
+#endif
+ break;
+ default:
+ mips_cpu.cputype = CPU_UNKNOWN;
+ break;
+ }
+ break;
+ default:
+ mips_cpu.cputype = CPU_UNKNOWN;
+ }
+ if (mips_cpu.options & MIPS_CPU_FPU)
+ mips_cpu.fpu_id = cpu_get_fpu_id();
+}
+
+__init void cpu_report(void)
+{
+ printk("CPU revision is: %08x\n", mips_cpu.processor_id);
+ if (mips_cpu.options & MIPS_CPU_FPU)
+ printk("FPU revision is: %08x\n", mips_cpu.fpu_id);
+}
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