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v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  linux/arch/m68k/mm/memory.c
  4 *
  5 *  Copyright (C) 1995  Hamish Macdonald
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/mm.h>
 10#include <linux/kernel.h>
 11#include <linux/string.h>
 12#include <linux/types.h>
 13#include <linux/init.h>
 14#include <linux/pagemap.h>
 15#include <linux/gfp.h>
 16
 17#include <asm/setup.h>
 
 18#include <asm/page.h>
 
 
 19#include <asm/traps.h>
 20#include <asm/machdep.h>
 21
 22
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 23/* invalidate page in both caches */
 24static inline void clear040(unsigned long paddr)
 25{
 26	asm volatile (
 27		"nop\n\t"
 28		".chip 68040\n\t"
 29		"cinvp %%bc,(%0)\n\t"
 30		".chip 68k"
 31		: : "a" (paddr));
 32}
 33
 34/* invalidate page in i-cache */
 35static inline void cleari040(unsigned long paddr)
 36{
 37	asm volatile (
 38		"nop\n\t"
 39		".chip 68040\n\t"
 40		"cinvp %%ic,(%0)\n\t"
 41		".chip 68k"
 42		: : "a" (paddr));
 43}
 44
 45/* push page in both caches */
 46/* RZ: cpush %bc DOES invalidate %ic, regardless of DPI */
 47static inline void push040(unsigned long paddr)
 48{
 49	asm volatile (
 50		"nop\n\t"
 51		".chip 68040\n\t"
 52		"cpushp %%bc,(%0)\n\t"
 53		".chip 68k"
 54		: : "a" (paddr));
 55}
 56
 57/* push and invalidate page in both caches, must disable ints
 58 * to avoid invalidating valid data */
 59static inline void pushcl040(unsigned long paddr)
 60{
 61	unsigned long flags;
 62
 63	local_irq_save(flags);
 64	push040(paddr);
 65	if (CPU_IS_060)
 66		clear040(paddr);
 67	local_irq_restore(flags);
 68}
 69
 70/*
 71 * 040: Hit every page containing an address in the range paddr..paddr+len-1.
 72 * (Low order bits of the ea of a CINVP/CPUSHP are "don't care"s).
 73 * Hit every page until there is a page or less to go. Hit the next page,
 74 * and the one after that if the range hits it.
 75 */
 76/* ++roman: A little bit more care is required here: The CINVP instruction
 77 * invalidates cache entries WITHOUT WRITING DIRTY DATA BACK! So the beginning
 78 * and the end of the region must be treated differently if they are not
 79 * exactly at the beginning or end of a page boundary. Else, maybe too much
 80 * data becomes invalidated and thus lost forever. CPUSHP does what we need:
 81 * it invalidates the page after pushing dirty data to memory. (Thanks to Jes
 82 * for discovering the problem!)
 83 */
 84/* ... but on the '060, CPUSH doesn't invalidate (for us, since we have set
 85 * the DPI bit in the CACR; would it cause problems with temporarily changing
 86 * this?). So we have to push first and then additionally to invalidate.
 87 */
 88
 89
 90/*
 91 * cache_clear() semantics: Clear any cache entries for the area in question,
 92 * without writing back dirty entries first. This is useful if the data will
 93 * be overwritten anyway, e.g. by DMA to memory. The range is defined by a
 94 * _physical_ address.
 95 */
 96
 97void cache_clear (unsigned long paddr, int len)
 98{
 99    if (CPU_IS_COLDFIRE) {
100	clear_cf_bcache(0, DCACHE_MAX_ADDR);
101    } else if (CPU_IS_040_OR_060) {
102	int tmp;
103
104	/*
105	 * We need special treatment for the first page, in case it
106	 * is not page-aligned. Page align the addresses to work
107	 * around bug I17 in the 68060.
108	 */
109	if ((tmp = -paddr & (PAGE_SIZE - 1))) {
110	    pushcl040(paddr & PAGE_MASK);
111	    if ((len -= tmp) <= 0)
112		return;
113	    paddr += tmp;
114	}
115	tmp = PAGE_SIZE;
116	paddr &= PAGE_MASK;
117	while ((len -= tmp) >= 0) {
118	    clear040(paddr);
119	    paddr += tmp;
120	}
121	if ((len += tmp))
122	    /* a page boundary gets crossed at the end */
123	    pushcl040(paddr);
124    }
125    else /* 68030 or 68020 */
126	asm volatile ("movec %/cacr,%/d0\n\t"
127		      "oriw %0,%/d0\n\t"
128		      "movec %/d0,%/cacr"
129		      : : "i" (FLUSH_I_AND_D)
130		      : "d0");
131#ifdef CONFIG_M68K_L2_CACHE
132    if(mach_l2_flush)
133	mach_l2_flush(0);
134#endif
135}
136EXPORT_SYMBOL(cache_clear);
137
138
139/*
140 * cache_push() semantics: Write back any dirty cache data in the given area,
141 * and invalidate the range in the instruction cache. It needs not (but may)
142 * invalidate those entries also in the data cache. The range is defined by a
143 * _physical_ address.
144 */
145
146void cache_push (unsigned long paddr, int len)
147{
148    if (CPU_IS_COLDFIRE) {
149	flush_cf_bcache(0, DCACHE_MAX_ADDR);
150    } else if (CPU_IS_040_OR_060) {
151	int tmp = PAGE_SIZE;
152
153	/*
154         * on 68040 or 68060, push cache lines for pages in the range;
155	 * on the '040 this also invalidates the pushed lines, but not on
156	 * the '060!
157	 */
158	len += paddr & (PAGE_SIZE - 1);
159
160	/*
161	 * Work around bug I17 in the 68060 affecting some instruction
162	 * lines not being invalidated properly.
163	 */
164	paddr &= PAGE_MASK;
165
166	do {
167	    push040(paddr);
168	    paddr += tmp;
169	} while ((len -= tmp) > 0);
170    }
171    /*
172     * 68030/68020 have no writeback cache. On the other hand,
173     * cache_push is actually a superset of cache_clear (the lines
174     * get written back and invalidated), so we should make sure
175     * to perform the corresponding actions. After all, this is getting
176     * called in places where we've just loaded code, or whatever, so
177     * flushing the icache is appropriate; flushing the dcache shouldn't
178     * be required.
179     */
180    else /* 68030 or 68020 */
181	asm volatile ("movec %/cacr,%/d0\n\t"
182		      "oriw %0,%/d0\n\t"
183		      "movec %/d0,%/cacr"
184		      : : "i" (FLUSH_I)
185		      : "d0");
186#ifdef CONFIG_M68K_L2_CACHE
187    if(mach_l2_flush)
188	mach_l2_flush(1);
189#endif
190}
191EXPORT_SYMBOL(cache_push);
192
v3.1
 
  1/*
  2 *  linux/arch/m68k/mm/memory.c
  3 *
  4 *  Copyright (C) 1995  Hamish Macdonald
  5 */
  6
  7#include <linux/module.h>
  8#include <linux/mm.h>
  9#include <linux/kernel.h>
 10#include <linux/string.h>
 11#include <linux/types.h>
 12#include <linux/init.h>
 13#include <linux/pagemap.h>
 14#include <linux/gfp.h>
 15
 16#include <asm/setup.h>
 17#include <asm/segment.h>
 18#include <asm/page.h>
 19#include <asm/pgalloc.h>
 20#include <asm/system.h>
 21#include <asm/traps.h>
 22#include <asm/machdep.h>
 23
 24
 25/* ++andreas: {get,free}_pointer_table rewritten to use unused fields from
 26   struct page instead of separately kmalloced struct.  Stolen from
 27   arch/sparc/mm/srmmu.c ... */
 28
 29typedef struct list_head ptable_desc;
 30static LIST_HEAD(ptable_list);
 31
 32#define PD_PTABLE(page) ((ptable_desc *)&(virt_to_page(page)->lru))
 33#define PD_PAGE(ptable) (list_entry(ptable, struct page, lru))
 34#define PD_MARKBITS(dp) (*(unsigned char *)&PD_PAGE(dp)->index)
 35
 36#define PTABLE_SIZE (PTRS_PER_PMD * sizeof(pmd_t))
 37
 38void __init init_pointer_table(unsigned long ptable)
 39{
 40	ptable_desc *dp;
 41	unsigned long page = ptable & PAGE_MASK;
 42	unsigned char mask = 1 << ((ptable - page)/PTABLE_SIZE);
 43
 44	dp = PD_PTABLE(page);
 45	if (!(PD_MARKBITS(dp) & mask)) {
 46		PD_MARKBITS(dp) = 0xff;
 47		list_add(dp, &ptable_list);
 48	}
 49
 50	PD_MARKBITS(dp) &= ~mask;
 51#ifdef DEBUG
 52	printk("init_pointer_table: %lx, %x\n", ptable, PD_MARKBITS(dp));
 53#endif
 54
 55	/* unreserve the page so it's possible to free that page */
 56	PD_PAGE(dp)->flags &= ~(1 << PG_reserved);
 57	init_page_count(PD_PAGE(dp));
 58
 59	return;
 60}
 61
 62pmd_t *get_pointer_table (void)
 63{
 64	ptable_desc *dp = ptable_list.next;
 65	unsigned char mask = PD_MARKBITS (dp);
 66	unsigned char tmp;
 67	unsigned int off;
 68
 69	/*
 70	 * For a pointer table for a user process address space, a
 71	 * table is taken from a page allocated for the purpose.  Each
 72	 * page can hold 8 pointer tables.  The page is remapped in
 73	 * virtual address space to be noncacheable.
 74	 */
 75	if (mask == 0) {
 76		void *page;
 77		ptable_desc *new;
 78
 79		if (!(page = (void *)get_zeroed_page(GFP_KERNEL)))
 80			return NULL;
 81
 82		flush_tlb_kernel_page(page);
 83		nocache_page(page);
 84
 85		new = PD_PTABLE(page);
 86		PD_MARKBITS(new) = 0xfe;
 87		list_add_tail(new, dp);
 88
 89		return (pmd_t *)page;
 90	}
 91
 92	for (tmp = 1, off = 0; (mask & tmp) == 0; tmp <<= 1, off += PTABLE_SIZE)
 93		;
 94	PD_MARKBITS(dp) = mask & ~tmp;
 95	if (!PD_MARKBITS(dp)) {
 96		/* move to end of list */
 97		list_move_tail(dp, &ptable_list);
 98	}
 99	return (pmd_t *) (page_address(PD_PAGE(dp)) + off);
100}
101
102int free_pointer_table (pmd_t *ptable)
103{
104	ptable_desc *dp;
105	unsigned long page = (unsigned long)ptable & PAGE_MASK;
106	unsigned char mask = 1 << (((unsigned long)ptable - page)/PTABLE_SIZE);
107
108	dp = PD_PTABLE(page);
109	if (PD_MARKBITS (dp) & mask)
110		panic ("table already free!");
111
112	PD_MARKBITS (dp) |= mask;
113
114	if (PD_MARKBITS(dp) == 0xff) {
115		/* all tables in page are free, free page */
116		list_del(dp);
117		cache_page((void *)page);
118		free_page (page);
119		return 1;
120	} else if (ptable_list.next != dp) {
121		/*
122		 * move this descriptor to the front of the list, since
123		 * it has one or more free tables.
124		 */
125		list_move(dp, &ptable_list);
126	}
127	return 0;
128}
129
130/* invalidate page in both caches */
131static inline void clear040(unsigned long paddr)
132{
133	asm volatile (
134		"nop\n\t"
135		".chip 68040\n\t"
136		"cinvp %%bc,(%0)\n\t"
137		".chip 68k"
138		: : "a" (paddr));
139}
140
141/* invalidate page in i-cache */
142static inline void cleari040(unsigned long paddr)
143{
144	asm volatile (
145		"nop\n\t"
146		".chip 68040\n\t"
147		"cinvp %%ic,(%0)\n\t"
148		".chip 68k"
149		: : "a" (paddr));
150}
151
152/* push page in both caches */
153/* RZ: cpush %bc DOES invalidate %ic, regardless of DPI */
154static inline void push040(unsigned long paddr)
155{
156	asm volatile (
157		"nop\n\t"
158		".chip 68040\n\t"
159		"cpushp %%bc,(%0)\n\t"
160		".chip 68k"
161		: : "a" (paddr));
162}
163
164/* push and invalidate page in both caches, must disable ints
165 * to avoid invalidating valid data */
166static inline void pushcl040(unsigned long paddr)
167{
168	unsigned long flags;
169
170	local_irq_save(flags);
171	push040(paddr);
172	if (CPU_IS_060)
173		clear040(paddr);
174	local_irq_restore(flags);
175}
176
177/*
178 * 040: Hit every page containing an address in the range paddr..paddr+len-1.
179 * (Low order bits of the ea of a CINVP/CPUSHP are "don't care"s).
180 * Hit every page until there is a page or less to go. Hit the next page,
181 * and the one after that if the range hits it.
182 */
183/* ++roman: A little bit more care is required here: The CINVP instruction
184 * invalidates cache entries WITHOUT WRITING DIRTY DATA BACK! So the beginning
185 * and the end of the region must be treated differently if they are not
186 * exactly at the beginning or end of a page boundary. Else, maybe too much
187 * data becomes invalidated and thus lost forever. CPUSHP does what we need:
188 * it invalidates the page after pushing dirty data to memory. (Thanks to Jes
189 * for discovering the problem!)
190 */
191/* ... but on the '060, CPUSH doesn't invalidate (for us, since we have set
192 * the DPI bit in the CACR; would it cause problems with temporarily changing
193 * this?). So we have to push first and then additionally to invalidate.
194 */
195
196
197/*
198 * cache_clear() semantics: Clear any cache entries for the area in question,
199 * without writing back dirty entries first. This is useful if the data will
200 * be overwritten anyway, e.g. by DMA to memory. The range is defined by a
201 * _physical_ address.
202 */
203
204void cache_clear (unsigned long paddr, int len)
205{
206    if (CPU_IS_040_OR_060) {
 
 
207	int tmp;
208
209	/*
210	 * We need special treatment for the first page, in case it
211	 * is not page-aligned. Page align the addresses to work
212	 * around bug I17 in the 68060.
213	 */
214	if ((tmp = -paddr & (PAGE_SIZE - 1))) {
215	    pushcl040(paddr & PAGE_MASK);
216	    if ((len -= tmp) <= 0)
217		return;
218	    paddr += tmp;
219	}
220	tmp = PAGE_SIZE;
221	paddr &= PAGE_MASK;
222	while ((len -= tmp) >= 0) {
223	    clear040(paddr);
224	    paddr += tmp;
225	}
226	if ((len += tmp))
227	    /* a page boundary gets crossed at the end */
228	    pushcl040(paddr);
229    }
230    else /* 68030 or 68020 */
231	asm volatile ("movec %/cacr,%/d0\n\t"
232		      "oriw %0,%/d0\n\t"
233		      "movec %/d0,%/cacr"
234		      : : "i" (FLUSH_I_AND_D)
235		      : "d0");
236#ifdef CONFIG_M68K_L2_CACHE
237    if(mach_l2_flush)
238	mach_l2_flush(0);
239#endif
240}
241EXPORT_SYMBOL(cache_clear);
242
243
244/*
245 * cache_push() semantics: Write back any dirty cache data in the given area,
246 * and invalidate the range in the instruction cache. It needs not (but may)
247 * invalidate those entries also in the data cache. The range is defined by a
248 * _physical_ address.
249 */
250
251void cache_push (unsigned long paddr, int len)
252{
253    if (CPU_IS_040_OR_060) {
 
 
254	int tmp = PAGE_SIZE;
255
256	/*
257         * on 68040 or 68060, push cache lines for pages in the range;
258	 * on the '040 this also invalidates the pushed lines, but not on
259	 * the '060!
260	 */
261	len += paddr & (PAGE_SIZE - 1);
262
263	/*
264	 * Work around bug I17 in the 68060 affecting some instruction
265	 * lines not being invalidated properly.
266	 */
267	paddr &= PAGE_MASK;
268
269	do {
270	    push040(paddr);
271	    paddr += tmp;
272	} while ((len -= tmp) > 0);
273    }
274    /*
275     * 68030/68020 have no writeback cache. On the other hand,
276     * cache_push is actually a superset of cache_clear (the lines
277     * get written back and invalidated), so we should make sure
278     * to perform the corresponding actions. After all, this is getting
279     * called in places where we've just loaded code, or whatever, so
280     * flushing the icache is appropriate; flushing the dcache shouldn't
281     * be required.
282     */
283    else /* 68030 or 68020 */
284	asm volatile ("movec %/cacr,%/d0\n\t"
285		      "oriw %0,%/d0\n\t"
286		      "movec %/d0,%/cacr"
287		      : : "i" (FLUSH_I)
288		      : "d0");
289#ifdef CONFIG_M68K_L2_CACHE
290    if(mach_l2_flush)
291	mach_l2_flush(1);
292#endif
293}
294EXPORT_SYMBOL(cache_push);
295