|  | // SPDX-License-Identifier: GPL-2.0 | 
|  | /* | 
|  | * Copyright (C) 2006 Chris Dearman (chris@mips.com), | 
|  | */ | 
|  | #include <linux/init.h> | 
|  | #include <linux/kernel.h> | 
|  | #include <linux/sched.h> | 
|  | #include <linux/mm.h> | 
|  |  | 
|  | #include <asm/cpu-type.h> | 
|  | #include <asm/mipsregs.h> | 
|  | #include <asm/bcache.h> | 
|  | #include <asm/cacheops.h> | 
|  | #include <asm/page.h> | 
|  | #include <asm/mmu_context.h> | 
|  | #include <asm/r4kcache.h> | 
|  | #include <asm/mips-cps.h> | 
|  | #include <asm/bootinfo.h> | 
|  |  | 
|  | /* | 
|  | * MIPS32/MIPS64 L2 cache handling | 
|  | */ | 
|  |  | 
|  | /* | 
|  | * Writeback and invalidate the secondary cache before DMA. | 
|  | */ | 
|  | static void mips_sc_wback_inv(unsigned long addr, unsigned long size) | 
|  | { | 
|  | blast_scache_range(addr, addr + size); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Invalidate the secondary cache before DMA. | 
|  | */ | 
|  | static void mips_sc_inv(unsigned long addr, unsigned long size) | 
|  | { | 
|  | unsigned long lsize = cpu_scache_line_size(); | 
|  | unsigned long almask = ~(lsize - 1); | 
|  |  | 
|  | cache_op(Hit_Writeback_Inv_SD, addr & almask); | 
|  | cache_op(Hit_Writeback_Inv_SD, (addr + size - 1) & almask); | 
|  | blast_inv_scache_range(addr, addr + size); | 
|  | } | 
|  |  | 
|  | static void mips_sc_enable(void) | 
|  | { | 
|  | /* L2 cache is permanently enabled */ | 
|  | } | 
|  |  | 
|  | static void mips_sc_disable(void) | 
|  | { | 
|  | /* L2 cache is permanently enabled */ | 
|  | } | 
|  |  | 
|  | static void mips_sc_prefetch_enable(void) | 
|  | { | 
|  | unsigned long pftctl; | 
|  |  | 
|  | if (mips_cm_revision() < CM_REV_CM2_5) | 
|  | return; | 
|  |  | 
|  | /* | 
|  | * If there is one or more L2 prefetch unit present then enable | 
|  | * prefetching for both code & data, for all ports. | 
|  | */ | 
|  | pftctl = read_gcr_l2_pft_control(); | 
|  | if (pftctl & CM_GCR_L2_PFT_CONTROL_NPFT) { | 
|  | pftctl &= ~CM_GCR_L2_PFT_CONTROL_PAGEMASK; | 
|  | pftctl |= PAGE_MASK & CM_GCR_L2_PFT_CONTROL_PAGEMASK; | 
|  | pftctl |= CM_GCR_L2_PFT_CONTROL_PFTEN; | 
|  | write_gcr_l2_pft_control(pftctl); | 
|  |  | 
|  | set_gcr_l2_pft_control_b(CM_GCR_L2_PFT_CONTROL_B_PORTID | | 
|  | CM_GCR_L2_PFT_CONTROL_B_CEN); | 
|  | } | 
|  | } | 
|  |  | 
|  | static void mips_sc_prefetch_disable(void) | 
|  | { | 
|  | if (mips_cm_revision() < CM_REV_CM2_5) | 
|  | return; | 
|  |  | 
|  | clear_gcr_l2_pft_control(CM_GCR_L2_PFT_CONTROL_PFTEN); | 
|  | clear_gcr_l2_pft_control_b(CM_GCR_L2_PFT_CONTROL_B_PORTID | | 
|  | CM_GCR_L2_PFT_CONTROL_B_CEN); | 
|  | } | 
|  |  | 
|  | static bool mips_sc_prefetch_is_enabled(void) | 
|  | { | 
|  | unsigned long pftctl; | 
|  |  | 
|  | if (mips_cm_revision() < CM_REV_CM2_5) | 
|  | return false; | 
|  |  | 
|  | pftctl = read_gcr_l2_pft_control(); | 
|  | if (!(pftctl & CM_GCR_L2_PFT_CONTROL_NPFT)) | 
|  | return false; | 
|  | return !!(pftctl & CM_GCR_L2_PFT_CONTROL_PFTEN); | 
|  | } | 
|  |  | 
|  | static struct bcache_ops mips_sc_ops = { | 
|  | .bc_enable = mips_sc_enable, | 
|  | .bc_disable = mips_sc_disable, | 
|  | .bc_wback_inv = mips_sc_wback_inv, | 
|  | .bc_inv = mips_sc_inv, | 
|  | .bc_prefetch_enable = mips_sc_prefetch_enable, | 
|  | .bc_prefetch_disable = mips_sc_prefetch_disable, | 
|  | .bc_prefetch_is_enabled = mips_sc_prefetch_is_enabled, | 
|  | }; | 
|  |  | 
|  | /* | 
|  | * Check if the L2 cache controller is activated on a particular platform. | 
|  | * MTI's L2 controller and the L2 cache controller of Broadcom's BMIPS | 
|  | * cores both use c0_config2's bit 12 as "L2 Bypass" bit, that is the | 
|  | * cache being disabled.  However there is no guarantee for this to be | 
|  | * true on all platforms.  In an act of stupidity the spec defined bits | 
|  | * 12..15 as implementation defined so below function will eventually have | 
|  | * to be replaced by a platform specific probe. | 
|  | */ | 
|  | static inline int mips_sc_is_activated(struct cpuinfo_mips *c) | 
|  | { | 
|  | unsigned int config2 = read_c0_config2(); | 
|  | unsigned int tmp; | 
|  |  | 
|  | /* Check the bypass bit (L2B) */ | 
|  | switch (current_cpu_type()) { | 
|  | case CPU_34K: | 
|  | case CPU_74K: | 
|  | case CPU_1004K: | 
|  | case CPU_1074K: | 
|  | case CPU_INTERAPTIV: | 
|  | case CPU_PROAPTIV: | 
|  | case CPU_P5600: | 
|  | case CPU_BMIPS5000: | 
|  | case CPU_QEMU_GENERIC: | 
|  | case CPU_P6600: | 
|  | if (config2 & (1 << 12)) | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | tmp = (config2 >> 4) & 0x0f; | 
|  | if (0 < tmp && tmp <= 7) | 
|  | c->scache.linesz = 2 << tmp; | 
|  | else | 
|  | return 0; | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | static int mips_sc_probe_cm3(void) | 
|  | { | 
|  | struct cpuinfo_mips *c = ¤t_cpu_data; | 
|  | unsigned long cfg = read_gcr_l2_config(); | 
|  | unsigned long sets, line_sz, assoc; | 
|  |  | 
|  | if (cfg & CM_GCR_L2_CONFIG_BYPASS) | 
|  | return 0; | 
|  |  | 
|  | sets = cfg & CM_GCR_L2_CONFIG_SET_SIZE; | 
|  | sets >>= __ffs(CM_GCR_L2_CONFIG_SET_SIZE); | 
|  | if (sets) | 
|  | c->scache.sets = 64 << sets; | 
|  |  | 
|  | line_sz = cfg & CM_GCR_L2_CONFIG_LINE_SIZE; | 
|  | line_sz >>= __ffs(CM_GCR_L2_CONFIG_LINE_SIZE); | 
|  | if (line_sz) | 
|  | c->scache.linesz = 2 << line_sz; | 
|  |  | 
|  | assoc = cfg & CM_GCR_L2_CONFIG_ASSOC; | 
|  | assoc >>= __ffs(CM_GCR_L2_CONFIG_ASSOC); | 
|  | c->scache.ways = assoc + 1; | 
|  | c->scache.waysize = c->scache.sets * c->scache.linesz; | 
|  | c->scache.waybit = __ffs(c->scache.waysize); | 
|  |  | 
|  | if (c->scache.linesz) { | 
|  | c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT; | 
|  | c->options |= MIPS_CPU_INCLUSIVE_CACHES; | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static inline int mips_sc_probe(void) | 
|  | { | 
|  | struct cpuinfo_mips *c = ¤t_cpu_data; | 
|  | unsigned int config1, config2; | 
|  | unsigned int tmp; | 
|  |  | 
|  | /* Mark as not present until probe completed */ | 
|  | c->scache.flags |= MIPS_CACHE_NOT_PRESENT; | 
|  |  | 
|  | if (mips_cm_revision() >= CM_REV_CM3) | 
|  | return mips_sc_probe_cm3(); | 
|  |  | 
|  | /* Ignore anything but MIPSxx processors */ | 
|  | if (!(c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 | | 
|  | MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 | | 
|  | MIPS_CPU_ISA_M32R5 | MIPS_CPU_ISA_M64R5 | | 
|  | MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))) | 
|  | return 0; | 
|  |  | 
|  | /* Does this MIPS32/MIPS64 CPU have a config2 register? */ | 
|  | config1 = read_c0_config1(); | 
|  | if (!(config1 & MIPS_CONF_M)) | 
|  | return 0; | 
|  |  | 
|  | config2 = read_c0_config2(); | 
|  |  | 
|  | if (!mips_sc_is_activated(c)) | 
|  | return 0; | 
|  |  | 
|  | tmp = (config2 >> 8) & 0x0f; | 
|  | if (tmp <= 7) | 
|  | c->scache.sets = 64 << tmp; | 
|  | else | 
|  | return 0; | 
|  |  | 
|  | tmp = (config2 >> 0) & 0x0f; | 
|  | if (tmp <= 7) | 
|  | c->scache.ways = tmp + 1; | 
|  | else | 
|  | return 0; | 
|  |  | 
|  | if (current_cpu_type() == CPU_XBURST) { | 
|  | switch (mips_machtype) { | 
|  | /* | 
|  | * According to config2 it would be 5-ways, but that is | 
|  | * contradicted by all documentation. | 
|  | */ | 
|  | case MACH_INGENIC_JZ4770: | 
|  | case MACH_INGENIC_JZ4775: | 
|  | c->scache.ways = 4; | 
|  | break; | 
|  |  | 
|  | /* | 
|  | * According to config2 it would be 5-ways and 512-sets, | 
|  | * but that is contradicted by all documentation. | 
|  | */ | 
|  | case MACH_INGENIC_X1000: | 
|  | case MACH_INGENIC_X1000E: | 
|  | c->scache.sets = 256; | 
|  | c->scache.ways = 4; | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | c->scache.waysize = c->scache.sets * c->scache.linesz; | 
|  | c->scache.waybit = __ffs(c->scache.waysize); | 
|  |  | 
|  | c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT; | 
|  |  | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | int mips_sc_init(void) | 
|  | { | 
|  | int found = mips_sc_probe(); | 
|  | if (found) { | 
|  | mips_sc_enable(); | 
|  | mips_sc_prefetch_enable(); | 
|  | bcops = &mips_sc_ops; | 
|  | } | 
|  | return found; | 
|  | } |