xref: /freebsd/sys/arm/arm/cpuinfo.c (revision 7bf5720a)

/*-
 * Copyright 2014 Svatopluk Kraus <onwahe@gmail.com>
 * Copyright 2014 Michal Meloun <meloun@miracle.cz>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysctl.h>

#include <machine/cpu.h>
#include <machine/cpuinfo.h>

#if __ARM_ARCH >= 6
void reinit_mmu(uint32_t ttb, uint32_t aux_clr, uint32_t aux_set);
#endif

struct cpuinfo cpuinfo =
{
	/* Use safe defaults for start */
	.dcache_line_size = 32,
	.dcache_line_mask = 31,
	.icache_line_size = 32,
	.icache_line_mask = 31,
};

static SYSCTL_NODE(_hw, OID_AUTO, cpu, CTLFLAG_RD, 0,
    "CPU");
static SYSCTL_NODE(_hw_cpu, OID_AUTO, quirks, CTLFLAG_RD, 0,
    "CPU quirks");

/*
 * Tunable CPU quirks.
 * Be careful, ACTRL cannot be changed if CPU is started in secure
 * mode(world) and write to ACTRL can cause exception!
 * These quirks are intended for optimizing CPU performance, not for
 * applying errata workarounds. Nobody can expect that CPU with unfixed
 * errata is stable enough to execute the kernel until quirks are applied.
 */
static uint32_t cpu_quirks_actlr_mask;
SYSCTL_INT(_hw_cpu_quirks, OID_AUTO, actlr_mask,
    CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &cpu_quirks_actlr_mask, 0,
    "Bits to be masked in ACTLR");

static uint32_t cpu_quirks_actlr_set;
SYSCTL_INT(_hw_cpu_quirks, OID_AUTO, actlr_set,
    CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &cpu_quirks_actlr_set, 0,
    "Bits to be set in ACTLR");


/* Read and parse CPU id scheme */
void
cpuinfo_init(void)
{

	cpuinfo.midr = cp15_midr_get();
	/* Test old version id schemes first */
	if ((cpuinfo.midr & CPU_ID_IMPLEMENTOR_MASK) == CPU_ID_ARM_LTD) {
		if (CPU_ID_ISOLD(cpuinfo.midr)) {
			/* obsolete ARMv2 or ARMv3 CPU */
			cpuinfo.midr = 0;
			return;
		}
		if (CPU_ID_IS7(cpuinfo.midr)) {
			if ((cpuinfo.midr & (1 << 23)) == 0) {
				/* obsolete ARMv3 CPU */
				cpuinfo.midr = 0;
				return;
			}
			/* ARMv4T CPU */
			cpuinfo.architecture = 1;
			cpuinfo.revision = (cpuinfo.midr >> 16) & 0x7F;
		} else {
			/* ARM new id scheme */
			cpuinfo.architecture = (cpuinfo.midr >> 16) & 0x0F;
			cpuinfo.revision = (cpuinfo.midr >> 20) & 0x0F;
		}
	} else {
		/* non ARM -> must be new id scheme */
		cpuinfo.architecture = (cpuinfo.midr >> 16) & 0x0F;
		cpuinfo.revision = (cpuinfo.midr >> 20) & 0x0F;
	}
	/* Parse rest of MIDR  */
	cpuinfo.implementer = (cpuinfo.midr >> 24) & 0xFF;
	cpuinfo.part_number = (cpuinfo.midr >> 4) & 0xFFF;
	cpuinfo.patch = cpuinfo.midr & 0x0F;

	/* CP15 c0,c0 regs 0-7 exist on all CPUs (although aliased with MIDR) */
	cpuinfo.ctr = cp15_ctr_get();
	cpuinfo.tcmtr = cp15_tcmtr_get();
#if __ARM_ARCH >= 6
	cpuinfo.tlbtr = cp15_tlbtr_get();
	cpuinfo.mpidr = cp15_mpidr_get();
	cpuinfo.revidr = cp15_revidr_get();
#endif

	/* if CPU is not v7 cpu id scheme */
	if (cpuinfo.architecture != 0xF)
		return;
#if __ARM_ARCH >= 6
	cpuinfo.id_pfr0 = cp15_id_pfr0_get();
	cpuinfo.id_pfr1 = cp15_id_pfr1_get();
	cpuinfo.id_dfr0 = cp15_id_dfr0_get();
	cpuinfo.id_afr0 = cp15_id_afr0_get();
	cpuinfo.id_mmfr0 = cp15_id_mmfr0_get();
	cpuinfo.id_mmfr1 = cp15_id_mmfr1_get();
	cpuinfo.id_mmfr2 = cp15_id_mmfr2_get();
	cpuinfo.id_mmfr3 = cp15_id_mmfr3_get();
	cpuinfo.id_isar0 = cp15_id_isar0_get();
	cpuinfo.id_isar1 = cp15_id_isar1_get();
	cpuinfo.id_isar2 = cp15_id_isar2_get();
	cpuinfo.id_isar3 = cp15_id_isar3_get();
	cpuinfo.id_isar4 = cp15_id_isar4_get();
	cpuinfo.id_isar5 = cp15_id_isar5_get();

/* Not yet - CBAR only exist on ARM SMP Cortex A CPUs
	cpuinfo.cbar = cp15_cbar_get();
*/
	if (CPU_CT_FORMAT(cpuinfo.ctr) == CPU_CT_ARMV7) {
		cpuinfo.ccsidr = cp15_ccsidr_get();
		cpuinfo.clidr = cp15_clidr_get();
	}

	/* Test if revidr is implemented */
	if (cpuinfo.revidr == cpuinfo.midr)
		cpuinfo.revidr = 0;

	/* parsed bits of above registers */
	/* id_mmfr0 */
	cpuinfo.outermost_shareability =  (cpuinfo.id_mmfr0 >> 8) & 0xF;
	cpuinfo.shareability_levels = (cpuinfo.id_mmfr0 >> 12) & 0xF;
	cpuinfo.auxiliary_registers = (cpuinfo.id_mmfr0 >> 20) & 0xF;
	cpuinfo.innermost_shareability = (cpuinfo.id_mmfr0 >> 28) & 0xF;
	/* id_mmfr2 */
	cpuinfo.mem_barrier = (cpuinfo.id_mmfr2 >> 20) & 0xF;
	/* id_mmfr3 */
	cpuinfo.coherent_walk = (cpuinfo.id_mmfr3 >> 20) & 0xF;
	cpuinfo.maintenance_broadcast =(cpuinfo.id_mmfr3 >> 12) & 0xF;
	/* id_pfr1 */
	cpuinfo.generic_timer_ext = (cpuinfo.id_pfr1 >> 16) & 0xF;
	cpuinfo.virtualization_ext = (cpuinfo.id_pfr1 >> 12) & 0xF;
	cpuinfo.security_ext = (cpuinfo.id_pfr1 >> 4) & 0xF;
	/* mpidr */
	cpuinfo.mp_ext = (cpuinfo.mpidr >> 31u) & 0x1;

	/* L1 Cache sizes */
	if (CPU_CT_FORMAT(cpuinfo.ctr) == CPU_CT_ARMV7) {
		cpuinfo.dcache_line_size =
		    1 << (CPU_CT_DMINLINE(cpuinfo.ctr) + 2);
		cpuinfo.icache_line_size =
		    1 << (CPU_CT_IMINLINE(cpuinfo.ctr) + 2);
	} else {
		cpuinfo.dcache_line_size =
		    1 << (CPU_CT_xSIZE_LEN(CPU_CT_DSIZE(cpuinfo.ctr)) + 3);
		cpuinfo.icache_line_size =
		    1 << (CPU_CT_xSIZE_LEN(CPU_CT_ISIZE(cpuinfo.ctr)) + 3);
	}
	cpuinfo.dcache_line_mask = cpuinfo.dcache_line_size - 1;
	cpuinfo.icache_line_mask = cpuinfo.icache_line_size - 1;
#endif
}

#if __ARM_ARCH >= 6
/*
 * Get bits that must be set or cleared in ACLR register.
 * Note: Bits in ACLR register are IMPLEMENTATION DEFINED.
 * Its expected that SCU is in operational state before this
 * function is called.
 */
static void
cpuinfo_get_actlr_modifier(uint32_t *actlr_mask, uint32_t *actlr_set)
{

	*actlr_mask = 0;
	*actlr_set = 0;

	if (cpuinfo.implementer == CPU_IMPLEMENTER_ARM) {
		switch (cpuinfo.part_number) {
		case CPU_ARCH_CORTEX_A73:
		case CPU_ARCH_CORTEX_A72:
		case CPU_ARCH_CORTEX_A57:
		case CPU_ARCH_CORTEX_A53:
			/* Nothing to do for AArch32 */
			break;
		case CPU_ARCH_CORTEX_A17:
		case CPU_ARCH_CORTEX_A12: /* A12 is merged to A17 */
			/*
			 * Enable SMP mode
			 */
			*actlr_mask = (1 << 6);
			*actlr_set = (1 << 6);
			break;
		case CPU_ARCH_CORTEX_A15:
			/*
			 * Enable snoop-delayed exclusive handling
			 * Enable SMP mode
			 */
			*actlr_mask = (1U << 31) |(1 << 6);
			*actlr_set = (1U << 31) |(1 << 6);
			break;
		case CPU_ARCH_CORTEX_A9:
			/*
			 * Disable exclusive L1/L2 cache control
			 * Enable SMP mode
			 * Enable Cache and TLB maintenance broadcast
			 */
			*actlr_mask = (1 << 7) | (1 << 6) | (1 << 0);
			*actlr_set = (1 << 6) | (1 << 0);
			break;
		case CPU_ARCH_CORTEX_A8:
			/*
			 * Enable L2 cache
			 * Enable L1 data cache hardware alias checks
			 */
			*actlr_mask = (1 << 1) | (1 << 0);
			*actlr_set = (1 << 1);
			break;
		case CPU_ARCH_CORTEX_A7:
			/*
			 * Enable SMP mode
			 */
			*actlr_mask = (1 << 6);
			*actlr_set = (1 << 6);
			break;
		case CPU_ARCH_CORTEX_A5:
			/*
			 * Disable exclusive L1/L2 cache control
			 * Enable SMP mode
			 * Enable Cache and TLB maintenance broadcast
			 */
			*actlr_mask = (1 << 7) | (1 << 6) | (1 << 0);
			*actlr_set = (1 << 6) | (1 << 0);
			break;
		case CPU_ARCH_ARM1176:
			/*
			 * Restrict cache size to 16KB
			 * Enable the return stack
			 * Enable dynamic branch prediction
			 * Enable static branch prediction
			 */
			*actlr_mask = (1 << 6) | (1 << 2) | (1 << 1) | (1 << 0);
			*actlr_set = (1 << 6) | (1 << 2) | (1 << 1) | (1 << 0);
			break;
		}
		return;
	}
}

/* Reinitialize MMU to final kernel mapping and apply all CPU quirks. */
void
cpuinfo_reinit_mmu(uint32_t ttb)
{
	uint32_t actlr_mask;
	uint32_t actlr_set;

	cpuinfo_get_actlr_modifier(&actlr_mask, &actlr_set);
	actlr_mask |= cpu_quirks_actlr_mask;
	actlr_set |= cpu_quirks_actlr_set;
	reinit_mmu(ttb, actlr_mask, actlr_set);
}

#endif /* __ARM_ARCH >= 6 */