Bryan Wu | 1394f03 | 2007-05-06 14:50:22 -0700 | [diff] [blame] | 1 | /* |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 2 | * arch/blackfin/lib/ins.S - ins{bwl} using hardware loops |
Bryan Wu | 1394f03 | 2007-05-06 14:50:22 -0700 | [diff] [blame] | 3 | * |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 4 | * Copyright 2004-2008 Analog Devices Inc. |
| 5 | * Copyright (C) 2005 Bas Vermeulen, BuyWays BV <bas@buyways.nl> |
| 6 | * Licensed under the GPL-2 or later. |
Bryan Wu | 1394f03 | 2007-05-06 14:50:22 -0700 | [diff] [blame] | 7 | */ |
| 8 | |
| 9 | #include <linux/linkage.h> |
Michael Hennerich | 8af10b7 | 2007-05-21 18:09:09 +0800 | [diff] [blame] | 10 | #include <asm/blackfin.h> |
Bryan Wu | 1394f03 | 2007-05-06 14:50:22 -0700 | [diff] [blame] | 11 | |
| 12 | .align 2 |
| 13 | |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 14 | #ifdef CONFIG_IPIPE |
| 15 | # define DO_CLI \ |
| 16 | [--sp] = rets; \ |
| 17 | [--sp] = (P5:0); \ |
| 18 | sp += -12; \ |
Philippe Gerum | b9c7eb4 | 2009-06-22 18:22:48 +0200 | [diff] [blame] | 19 | call ___ipipe_disable_root_irqs_hw; \ |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 20 | sp += 12; \ |
| 21 | (P5:0) = [sp++]; |
| 22 | # define CLI_INNER_NOP |
| 23 | #else |
| 24 | # define DO_CLI cli R3; |
| 25 | # define CLI_INNER_NOP nop; nop; nop; |
| 26 | #endif |
| 27 | |
| 28 | #ifdef CONFIG_IPIPE |
| 29 | # define DO_STI \ |
| 30 | sp += -12; \ |
Philippe Gerum | b9c7eb4 | 2009-06-22 18:22:48 +0200 | [diff] [blame] | 31 | call ___ipipe_enable_root_irqs_hw; \ |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 32 | sp += 12; \ |
| 33 | 2: rets = [sp++]; |
| 34 | #else |
| 35 | # define DO_STI 2: sti R3; |
| 36 | #endif |
| 37 | |
| 38 | #ifdef CONFIG_BFIN_INS_LOWOVERHEAD |
| 39 | # define CLI_OUTER DO_CLI; |
| 40 | # define STI_OUTER DO_STI; |
| 41 | # define CLI_INNER 1: |
| 42 | # if ANOMALY_05000416 |
| 43 | # define STI_INNER nop; 2: nop; |
| 44 | # else |
| 45 | # define STI_INNER 2: |
| 46 | # endif |
| 47 | #else |
| 48 | # define CLI_OUTER |
| 49 | # define STI_OUTER |
| 50 | # define CLI_INNER 1: DO_CLI; CLI_INNER_NOP; |
| 51 | # define STI_INNER DO_STI; |
| 52 | #endif |
| 53 | |
Robin Getz | 251383c | 2008-08-14 15:12:55 +0800 | [diff] [blame] | 54 | /* |
| 55 | * Reads on the Blackfin are speculative. In Blackfin terms, this means they |
| 56 | * can be interrupted at any time (even after they have been issued on to the |
| 57 | * external bus), and re-issued after the interrupt occurs. |
| 58 | * |
| 59 | * If a FIFO is sitting on the end of the read, it will see two reads, |
| 60 | * when the core only sees one. The FIFO receives the read which is cancelled, |
| 61 | * and not delivered to the core. |
| 62 | * |
| 63 | * To solve this, interrupts are turned off before reads occur to I/O space. |
| 64 | * There are 3 versions of all these functions |
| 65 | * - turns interrupts off every read (higher overhead, but lower latency) |
| 66 | * - turns interrupts off every loop (low overhead, but longer latency) |
| 67 | * - DMA version, which do not suffer from this issue. DMA versions have |
| 68 | * different name (prefixed by dma_ ), and are located in |
| 69 | * ../kernel/bfin_dma_5xx.c |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 70 | * Using the dma related functions are recommended for transferring large |
Robin Getz | 251383c | 2008-08-14 15:12:55 +0800 | [diff] [blame] | 71 | * buffers in/out of FIFOs. |
| 72 | */ |
| 73 | |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 74 | #define COMMON_INS(func, ops) \ |
| 75 | ENTRY(_ins##func) \ |
| 76 | P0 = R0; /* P0 = port */ \ |
| 77 | CLI_OUTER; /* 3 instructions before first read access */ \ |
| 78 | P1 = R1; /* P1 = address */ \ |
| 79 | P2 = R2; /* P2 = count */ \ |
| 80 | SSYNC; \ |
| 81 | \ |
| 82 | LSETUP(1f, 2f) LC0 = P2; \ |
| 83 | CLI_INNER; \ |
| 84 | ops; \ |
| 85 | STI_INNER; \ |
| 86 | \ |
| 87 | STI_OUTER; \ |
| 88 | RTS; \ |
| 89 | ENDPROC(_ins##func) |
Michael Hennerich | 8af10b7 | 2007-05-21 18:09:09 +0800 | [diff] [blame] | 90 | |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 91 | COMMON_INS(l, \ |
| 92 | R0 = [P0]; \ |
| 93 | [P1++] = R0; \ |
| 94 | ) |
Robin Getz | 251383c | 2008-08-14 15:12:55 +0800 | [diff] [blame] | 95 | |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 96 | COMMON_INS(w, \ |
| 97 | R0 = W[P0]; \ |
| 98 | W[P1++] = R0; \ |
| 99 | ) |
Bryan Wu | 1394f03 | 2007-05-06 14:50:22 -0700 | [diff] [blame] | 100 | |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 101 | COMMON_INS(w_8, \ |
| 102 | R0 = W[P0]; \ |
| 103 | B[P1++] = R0; \ |
| 104 | R0 = R0 >> 8; \ |
| 105 | B[P1++] = R0; \ |
| 106 | ) |
Michael Hennerich | 5906967 | 2008-05-17 16:38:52 +0800 | [diff] [blame] | 107 | |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 108 | COMMON_INS(b, \ |
| 109 | R0 = B[P0]; \ |
| 110 | B[P1++] = R0; \ |
| 111 | ) |
Michael Hennerich | 5c91fb9 | 2007-11-17 23:46:58 +0800 | [diff] [blame] | 112 | |
Mike Frysinger | c250bfb | 2009-01-07 23:14:38 +0800 | [diff] [blame] | 113 | COMMON_INS(l_16, \ |
| 114 | R0 = [P0]; \ |
| 115 | W[P1++] = R0; \ |
| 116 | R0 = R0 >> 16; \ |
| 117 | W[P1++] = R0; \ |
| 118 | ) |