csky/kernel/io.c

0001 // SPDX-License-Identifier: GPL-2.0
0002
0003 #include <linux/export.h>
0004 #include <linux/types.h>
0005 #include <linux/io.h>
0006
0007 /*
0008  * Copy data from IO memory space to "real" memory space.
0009  */
0010 void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t count)
0011 {
0012     while (count && !IS_ALIGNED((unsigned long)from, 4)) {
0013         *(u8 *)to = __raw_readb(from);
0014         from++;
0015         to++;
0016         count--;
0017     }
0018
0019     while (count >= 4) {
0020         *(u32 *)to = __raw_readl(from);
0021         from += 4;
0022         to += 4;
0023         count -= 4;
0024     }
0025
0026     while (count) {
0027         *(u8 *)to = __raw_readb(from);
0028         from++;
0029         to++;
0030         count--;
0031     }
0032 }
0033 EXPORT_SYMBOL(__memcpy_fromio);
0034
0035 /*
0036  * Copy data from "real" memory space to IO memory space.
0037  */
0038 void __memcpy_toio(volatile void __iomem *to, const void *from, size_t count)
0039 {
0040     while (count && !IS_ALIGNED((unsigned long)to, 4)) {
0041         __raw_writeb(*(u8 *)from, to);
0042         from++;
0043         to++;
0044         count--;
0045     }
0046
0047     while (count >= 4) {
0048         __raw_writel(*(u32 *)from, to);
0049         from += 4;
0050         to += 4;
0051         count -= 4;
0052     }
0053
0054     while (count) {
0055         __raw_writeb(*(u8 *)from, to);
0056         from++;
0057         to++;
0058         count--;
0059     }
0060 }
0061 EXPORT_SYMBOL(__memcpy_toio);
0062
0063 /*
0064  * "memset" on IO memory space.
0065  */
0066 void __memset_io(volatile void __iomem *dst, int c, size_t count)
0067 {
0068     u32 qc = (u8)c;
0069
0070     qc |= qc << 8;
0071     qc |= qc << 16;
0072
0073     while (count && !IS_ALIGNED((unsigned long)dst, 4)) {
0074         __raw_writeb(c, dst);
0075         dst++;
0076         count--;
0077     }
0078
0079     while (count >= 4) {
0080         __raw_writel(qc, dst);
0081         dst += 4;
0082         count -= 4;
0083     }
0084
0085     while (count) {
0086         __raw_writeb(c, dst);
0087         dst++;
0088         count--;
0089     }
0090 }
0091 EXPORT_SYMBOL(__memset_io);