2 * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
3 * Copyright (C) 1997, 2001 Ralf Baechle (ralf@gnu.org)
4 * Copyright (C) 2000 SiByte, Inc.
5 * Copyright (C) 2005 Thiemo Seufer
7 * Written by Justin Carlson of SiByte, Inc.
8 * and Kip Walker of Broadcom Corp.
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version 2
14 * of the License, or (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 #include <linux/module.h>
26 #include <linux/sched.h>
27 #include <linux/smp.h>
30 #include <asm/sibyte/sb1250.h>
31 #include <asm/sibyte/sb1250_regs.h>
32 #include <asm/sibyte/sb1250_dma.h>
34 #ifdef CONFIG_SB1_PASS_1_WORKAROUNDS
35 #define SB1_PREF_LOAD_STREAMED_HINT "0"
36 #define SB1_PREF_STORE_STREAMED_HINT "1"
38 #define SB1_PREF_LOAD_STREAMED_HINT "4"
39 #define SB1_PREF_STORE_STREAMED_HINT "5"
42 static inline void clear_page_cpu(void *page)
44 unsigned char *addr = (unsigned char *) page;
45 unsigned char *end = addr + PAGE_SIZE;
48 * JDCXXX - This should be bottlenecked by the write buffer, but these
49 * things tend to be mildly unpredictable...should check this on the
52 * We prefetch 4 lines ahead. We're also "cheating" slightly here...
53 * since we know we're on an SB1, we force the assembler to take
54 * 64-bit operands to speed things up
60 #ifdef CONFIG_CPU_HAS_PREFETCH
61 " daddiu %0, %0, 128 \n"
62 " pref " SB1_PREF_STORE_STREAMED_HINT ", -128(%0) \n"
63 /* Prefetch the first 4 lines */
64 " pref " SB1_PREF_STORE_STREAMED_HINT ", -96(%0) \n"
65 " pref " SB1_PREF_STORE_STREAMED_HINT ", -64(%0) \n"
66 " pref " SB1_PREF_STORE_STREAMED_HINT ", -32(%0) \n"
67 "1: sd $0, -128(%0) \n" /* Throw out a cacheline of 0's */
71 " daddiu %0, %0, 32 \n"
73 " pref " SB1_PREF_STORE_STREAMED_HINT ", -32(%0) \n"
74 " daddiu %0, %0, -128 \n"
76 " sd $0, 0(%0) \n" /* Throw out a cacheline of 0's */
80 " daddiu %0, %0, 32 \n"
89 static inline void copy_page_cpu(void *to, void *from)
91 unsigned char *src = (unsigned char *)from;
92 unsigned char *dst = (unsigned char *)to;
93 unsigned char *end = src + PAGE_SIZE;
96 * The pref's used here are using "streaming" hints, which cause the
97 * copied data to be kicked out of the cache sooner. A page copy often
98 * ends up copying a lot more data than is commonly used, so this seems
99 * to make sense in terms of reducing cache pollution, but I've no real
100 * performance data to back this up
102 __asm__ __volatile__(
106 #ifdef CONFIG_CPU_HAS_PREFETCH
107 " daddiu %0, %0, 128 \n"
108 " daddiu %1, %1, 128 \n"
109 " pref " SB1_PREF_LOAD_STREAMED_HINT ", -128(%0)\n"
110 /* Prefetch the first 4 lines */
111 " pref " SB1_PREF_STORE_STREAMED_HINT ", -128(%1)\n"
112 " pref " SB1_PREF_LOAD_STREAMED_HINT ", -96(%0)\n"
113 " pref " SB1_PREF_STORE_STREAMED_HINT ", -96(%1)\n"
114 " pref " SB1_PREF_LOAD_STREAMED_HINT ", -64(%0)\n"
115 " pref " SB1_PREF_STORE_STREAMED_HINT ", -64(%1)\n"
116 " pref " SB1_PREF_LOAD_STREAMED_HINT ", -32(%0)\n"
117 "1: pref " SB1_PREF_STORE_STREAMED_HINT ", -32(%1)\n"
119 " ld $8, -128(%0) \n" /* Block copy a cacheline */
120 " ld $9, -120(%0) \n"
121 " ld $10, -112(%0) \n"
122 " ld $11, -104(%0) \n"
123 " sd $8, -128(%1) \n"
124 " sd $9, -120(%1) \n"
125 " sd $10, -112(%1) \n"
126 " sd $11, -104(%1) \n"
128 " lw $2, -128(%0) \n" /* Block copy a cacheline */
129 " lw $3, -124(%0) \n"
130 " lw $6, -120(%0) \n"
131 " lw $7, -116(%0) \n"
132 " lw $8, -112(%0) \n"
133 " lw $9, -108(%0) \n"
134 " lw $10, -104(%0) \n"
135 " lw $11, -100(%0) \n"
136 " sw $2, -128(%1) \n"
137 " sw $3, -124(%1) \n"
138 " sw $6, -120(%1) \n"
139 " sw $7, -116(%1) \n"
140 " sw $8, -112(%1) \n"
141 " sw $9, -108(%1) \n"
142 " sw $10, -104(%1) \n"
143 " sw $11, -100(%1) \n"
145 " daddiu %0, %0, 32 \n"
146 " daddiu %1, %1, 32 \n"
147 " bnel %0, %2, 1b \n"
148 " pref " SB1_PREF_LOAD_STREAMED_HINT ", -32(%0)\n"
149 " daddiu %0, %0, -128 \n"
150 " daddiu %1, %1, -128 \n"
153 " ld $8, 0(%0) \n" /* Block copy a cacheline */
162 " lw $2, 0(%0) \n" /* Block copy a cacheline */
179 " daddiu %0, %0, 32 \n"
180 " daddiu %1, %1, 32 \n"
181 " bnel %0, %2, 1b \n"
188 : "+r" (src), "+r" (dst)
191 : "$8","$9","$10","$11","memory");
193 : "$2","$3","$6","$7","$8","$9","$10","$11","memory");
198 #ifdef CONFIG_SIBYTE_DMA_PAGEOPS
201 * Pad descriptors to cacheline, since each is exclusively owned by a
204 typedef struct dmadscr_s {
211 static dmadscr_t page_descr[DM_NUM_CHANNELS]
212 __attribute__((aligned(SMP_CACHE_BYTES)));
214 void sb1_dma_init(void)
218 for (i = 0; i < DM_NUM_CHANNELS; i++) {
219 const u64 base_val = CPHYSADDR(&page_descr[i]) |
220 V_DM_DSCR_BASE_RINGSZ(1);
221 volatile void *base_reg =
222 IOADDR(A_DM_REGISTER(i, R_DM_DSCR_BASE));
224 __raw_writeq(base_val, base_reg);
225 __raw_writeq(base_val | M_DM_DSCR_BASE_RESET, base_reg);
226 __raw_writeq(base_val | M_DM_DSCR_BASE_ENABL, base_reg);
230 void clear_page(void *page)
232 u64 to_phys = CPHYSADDR(page);
233 unsigned int cpu = smp_processor_id();
235 /* if the page is not in KSEG0, use old way */
236 if ((long)KSEGX(page) != (long)CKSEG0)
237 return clear_page_cpu(page);
239 page_descr[cpu].dscr_a = to_phys | M_DM_DSCRA_ZERO_MEM |
240 M_DM_DSCRA_L2C_DEST | M_DM_DSCRA_INTERRUPT;
241 page_descr[cpu].dscr_b = V_DM_DSCRB_SRC_LENGTH(PAGE_SIZE);
242 __raw_writeq(1, IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_COUNT)));
245 * Don't really want to do it this way, but there's no
246 * reliable way to delay completion detection.
248 while (!(__raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE_DEBUG)))
249 & M_DM_DSCR_BASE_INTERRUPT))
251 __raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE)));
254 void copy_page(void *to, void *from)
256 u64 from_phys = CPHYSADDR(from);
257 u64 to_phys = CPHYSADDR(to);
258 unsigned int cpu = smp_processor_id();
260 /* if any page is not in KSEG0, use old way */
261 if ((long)KSEGX(to) != (long)CKSEG0
262 || (long)KSEGX(from) != (long)CKSEG0)
263 return copy_page_cpu(to, from);
265 page_descr[cpu].dscr_a = to_phys | M_DM_DSCRA_L2C_DEST |
266 M_DM_DSCRA_INTERRUPT;
267 page_descr[cpu].dscr_b = from_phys | V_DM_DSCRB_SRC_LENGTH(PAGE_SIZE);
268 __raw_writeq(1, IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_COUNT)));
271 * Don't really want to do it this way, but there's no
272 * reliable way to delay completion detection.
274 while (!(__raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE_DEBUG)))
275 & M_DM_DSCR_BASE_INTERRUPT))
277 __raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE)));
280 #else /* !CONFIG_SIBYTE_DMA_PAGEOPS */
282 void clear_page(void *page)
284 return clear_page_cpu(page);
287 void copy_page(void *to, void *from)
289 return copy_page_cpu(to, from);
292 #endif /* !CONFIG_SIBYTE_DMA_PAGEOPS */
294 EXPORT_SYMBOL(clear_page);
295 EXPORT_SYMBOL(copy_page);