diff options
author | Lennert Buytenhek <buytenh@wantstofly.org> | 2005-11-01 19:53:50 +0000 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2005-11-01 19:53:50 +0000 |
commit | d01e8897fcf597f62d84f626fdced8d94c70deaf (patch) | |
tree | 72e25f7df9b10aec46ccca594414f91eef092860 /arch/arm/mach-ixp2000 | |
parent | fadab0943d1c5b652a66858bb99b204fedaad96b (diff) | |
download | linux-d01e8897fcf597f62d84f626fdced8d94c70deaf.tar.bz2 |
[ARM] 3052/1: add ixp2000 microcode loader
Patch from Lennert Buytenhek
This patch adds a microcode loader for the ixp2000 architecture.
The ixp2000 is an xscale-based CPU with a number of additional small
CPUs ('microengines') on die that can be programmed to do various
things. Depending on the ixp2000 model, there are between 2 and 16
microengines.
This code provides an API that allows configuring the microengines,
loading code into them, and starting and stopping them and reading
out a number of status registers, and is used by the microengine
network driver that was recently announced to netdev.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mach-ixp2000')
-rw-r--r-- | arch/arm/mach-ixp2000/Makefile | 2 | ||||
-rw-r--r-- | arch/arm/mach-ixp2000/uengine.c | 474 |
2 files changed, 475 insertions, 1 deletions
diff --git a/arch/arm/mach-ixp2000/Makefile b/arch/arm/mach-ixp2000/Makefile index 1e6139d42a92..9621aeb61f46 100644 --- a/arch/arm/mach-ixp2000/Makefile +++ b/arch/arm/mach-ixp2000/Makefile @@ -1,7 +1,7 @@ # # Makefile for the linux kernel. # -obj-y := core.o pci.o +obj-y := core.o pci.o uengine.o obj-m := obj-n := obj- := diff --git a/arch/arm/mach-ixp2000/uengine.c b/arch/arm/mach-ixp2000/uengine.c new file mode 100644 index 000000000000..43e234349d4a --- /dev/null +++ b/arch/arm/mach-ixp2000/uengine.c @@ -0,0 +1,474 @@ +/* + * Generic library functions for the microengines found on the Intel + * IXP2000 series of network processors. + * + * Copyright (C) 2004, 2005 Lennert Buytenhek <buytenh@wantstofly.org> + * Dedicated to Marija Kulikova. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of the + * License, or (at your option) any later version. + */ + +#include <linux/config.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/string.h> +#include <asm/hardware.h> +#include <asm/arch/ixp2000-regs.h> +#include <asm/arch/uengine.h> +#include <asm/io.h> + +#define USTORE_ADDRESS 0x000 +#define USTORE_DATA_LOWER 0x004 +#define USTORE_DATA_UPPER 0x008 +#define CTX_ENABLES 0x018 +#define CC_ENABLE 0x01c +#define CSR_CTX_POINTER 0x020 +#define INDIRECT_CTX_STS 0x040 +#define ACTIVE_CTX_STS 0x044 +#define INDIRECT_CTX_SIG_EVENTS 0x048 +#define INDIRECT_CTX_WAKEUP_EVENTS 0x050 +#define NN_PUT 0x080 +#define NN_GET 0x084 +#define TIMESTAMP_LOW 0x0c0 +#define TIMESTAMP_HIGH 0x0c4 +#define T_INDEX_BYTE_INDEX 0x0f4 +#define LOCAL_CSR_STATUS 0x180 + +u32 ixp2000_uengine_mask; + +static void *ixp2000_uengine_csr_area(int uengine) +{ + return ((void *)IXP2000_UENGINE_CSR_VIRT_BASE) + (uengine << 10); +} + +/* + * LOCAL_CSR_STATUS=1 after a read or write to a microengine's CSR + * space means that the microengine we tried to access was also trying + * to access its own CSR space on the same clock cycle as we did. When + * this happens, we lose the arbitration process by default, and the + * read or write we tried to do was not actually performed, so we try + * again until it succeeds. + */ +u32 ixp2000_uengine_csr_read(int uengine, int offset) +{ + void *uebase; + u32 *local_csr_status; + u32 *reg; + u32 value; + + uebase = ixp2000_uengine_csr_area(uengine); + + local_csr_status = (u32 *)(uebase + LOCAL_CSR_STATUS); + reg = (u32 *)(uebase + offset); + do { + value = ixp2000_reg_read(reg); + } while (ixp2000_reg_read(local_csr_status) & 1); + + return value; +} +EXPORT_SYMBOL(ixp2000_uengine_csr_read); + +void ixp2000_uengine_csr_write(int uengine, int offset, u32 value) +{ + void *uebase; + u32 *local_csr_status; + u32 *reg; + + uebase = ixp2000_uengine_csr_area(uengine); + + local_csr_status = (u32 *)(uebase + LOCAL_CSR_STATUS); + reg = (u32 *)(uebase + offset); + do { + ixp2000_reg_write(reg, value); + } while (ixp2000_reg_read(local_csr_status) & 1); +} +EXPORT_SYMBOL(ixp2000_uengine_csr_write); + +void ixp2000_uengine_reset(u32 uengine_mask) +{ + ixp2000_reg_write(IXP2000_RESET1, uengine_mask & ixp2000_uengine_mask); + ixp2000_reg_write(IXP2000_RESET1, 0); +} +EXPORT_SYMBOL(ixp2000_uengine_reset); + +void ixp2000_uengine_set_mode(int uengine, u32 mode) +{ + /* + * CTL_STR_PAR_EN: unconditionally enable parity checking on + * control store. + */ + mode |= 0x10000000; + ixp2000_uengine_csr_write(uengine, CTX_ENABLES, mode); + + /* + * Enable updating of condition codes. + */ + ixp2000_uengine_csr_write(uengine, CC_ENABLE, 0x00002000); + + /* + * Initialise other per-microengine registers. + */ + ixp2000_uengine_csr_write(uengine, NN_PUT, 0x00); + ixp2000_uengine_csr_write(uengine, NN_GET, 0x00); + ixp2000_uengine_csr_write(uengine, T_INDEX_BYTE_INDEX, 0); +} +EXPORT_SYMBOL(ixp2000_uengine_set_mode); + +static int make_even_parity(u32 x) +{ + return hweight32(x) & 1; +} + +static void ustore_write(int uengine, u64 insn) +{ + /* + * Generate even parity for top and bottom 20 bits. + */ + insn |= (u64)make_even_parity((insn >> 20) & 0x000fffff) << 41; + insn |= (u64)make_even_parity(insn & 0x000fffff) << 40; + + /* + * Write to microstore. The second write auto-increments + * the USTORE_ADDRESS index register. + */ + ixp2000_uengine_csr_write(uengine, USTORE_DATA_LOWER, (u32)insn); + ixp2000_uengine_csr_write(uengine, USTORE_DATA_UPPER, (u32)(insn >> 32)); +} + +void ixp2000_uengine_load_microcode(int uengine, u8 *ucode, int insns) +{ + int i; + + /* + * Start writing to microstore at address 0. + */ + ixp2000_uengine_csr_write(uengine, USTORE_ADDRESS, 0x80000000); + for (i = 0; i < insns; i++) { + u64 insn; + + insn = (((u64)ucode[0]) << 32) | + (((u64)ucode[1]) << 24) | + (((u64)ucode[2]) << 16) | + (((u64)ucode[3]) << 8) | + ((u64)ucode[4]); + ucode += 5; + + ustore_write(uengine, insn); + } + + /* + * Pad with a few NOPs at the end (to avoid the microengine + * aborting as it prefetches beyond the last instruction), unless + * we run off the end of the instruction store first, at which + * point the address register will wrap back to zero. + */ + for (i = 0; i < 4; i++) { + u32 addr; + + addr = ixp2000_uengine_csr_read(uengine, USTORE_ADDRESS); + if (addr == 0x80000000) + break; + ustore_write(uengine, 0xf0000c0300ULL); + } + + /* + * End programming. + */ + ixp2000_uengine_csr_write(uengine, USTORE_ADDRESS, 0x00000000); +} +EXPORT_SYMBOL(ixp2000_uengine_load_microcode); + +void ixp2000_uengine_init_context(int uengine, int context, int pc) +{ + /* + * Select the right context for indirect access. + */ + ixp2000_uengine_csr_write(uengine, CSR_CTX_POINTER, context); + + /* + * Initialise signal masks to immediately go to Ready state. + */ + ixp2000_uengine_csr_write(uengine, INDIRECT_CTX_SIG_EVENTS, 1); + ixp2000_uengine_csr_write(uengine, INDIRECT_CTX_WAKEUP_EVENTS, 1); + + /* + * Set program counter. + */ + ixp2000_uengine_csr_write(uengine, INDIRECT_CTX_STS, pc); +} +EXPORT_SYMBOL(ixp2000_uengine_init_context); + +void ixp2000_uengine_start_contexts(int uengine, u8 ctx_mask) +{ + u32 mask; + + /* + * Enable the specified context to go to Executing state. + */ + mask = ixp2000_uengine_csr_read(uengine, CTX_ENABLES); + mask |= ctx_mask << 8; + ixp2000_uengine_csr_write(uengine, CTX_ENABLES, mask); +} +EXPORT_SYMBOL(ixp2000_uengine_start_contexts); + +void ixp2000_uengine_stop_contexts(int uengine, u8 ctx_mask) +{ + u32 mask; + + /* + * Disable the Ready->Executing transition. Note that this + * does not stop the context until it voluntarily yields. + */ + mask = ixp2000_uengine_csr_read(uengine, CTX_ENABLES); + mask &= ~(ctx_mask << 8); + ixp2000_uengine_csr_write(uengine, CTX_ENABLES, mask); +} +EXPORT_SYMBOL(ixp2000_uengine_stop_contexts); + +static int check_ixp_type(struct ixp2000_uengine_code *c) +{ + u32 product_id; + u32 rev; + + product_id = ixp2000_reg_read(IXP2000_PRODUCT_ID); + if (((product_id >> 16) & 0x1f) != 0) + return 0; + + switch ((product_id >> 8) & 0xff) { + case 0: /* IXP2800 */ + if (!(c->cpu_model_bitmask & 4)) + return 0; + break; + + case 1: /* IXP2850 */ + if (!(c->cpu_model_bitmask & 8)) + return 0; + break; + + case 2: /* IXP2400 */ + if (!(c->cpu_model_bitmask & 2)) + return 0; + break; + + default: + return 0; + } + + rev = product_id & 0xff; + if (rev < c->cpu_min_revision || rev > c->cpu_max_revision) + return 0; + + return 1; +} + +static void generate_ucode(u8 *ucode, u32 *gpr_a, u32 *gpr_b) +{ + int offset; + int i; + + offset = 0; + + for (i = 0; i < 128; i++) { + u8 b3; + u8 b2; + u8 b1; + u8 b0; + + b3 = (gpr_a[i] >> 24) & 0xff; + b2 = (gpr_a[i] >> 16) & 0xff; + b1 = (gpr_a[i] >> 8) & 0xff; + b0 = gpr_a[i] & 0xff; + + // immed[@ai, (b1 << 8) | b0] + // 11110000 0000VVVV VVVV11VV VVVVVV00 1IIIIIII + ucode[offset++] = 0xf0; + ucode[offset++] = (b1 >> 4); + ucode[offset++] = (b1 << 4) | 0x0c | (b0 >> 6); + ucode[offset++] = (b0 << 2); + ucode[offset++] = 0x80 | i; + + // immed_w1[@ai, (b3 << 8) | b2] + // 11110100 0100VVVV VVVV11VV VVVVVV00 1IIIIIII + ucode[offset++] = 0xf4; + ucode[offset++] = 0x40 | (b3 >> 4); + ucode[offset++] = (b3 << 4) | 0x0c | (b2 >> 6); + ucode[offset++] = (b2 << 2); + ucode[offset++] = 0x80 | i; + } + + for (i = 0; i < 128; i++) { + u8 b3; + u8 b2; + u8 b1; + u8 b0; + + b3 = (gpr_b[i] >> 24) & 0xff; + b2 = (gpr_b[i] >> 16) & 0xff; + b1 = (gpr_b[i] >> 8) & 0xff; + b0 = gpr_b[i] & 0xff; + + // immed[@bi, (b1 << 8) | b0] + // 11110000 0000VVVV VVVV001I IIIIII11 VVVVVVVV + ucode[offset++] = 0xf0; + ucode[offset++] = (b1 >> 4); + ucode[offset++] = (b1 << 4) | 0x02 | (i >> 6); + ucode[offset++] = (i << 2) | 0x03; + ucode[offset++] = b0; + + // immed_w1[@bi, (b3 << 8) | b2] + // 11110100 0100VVVV VVVV001I IIIIII11 VVVVVVVV + ucode[offset++] = 0xf4; + ucode[offset++] = 0x40 | (b3 >> 4); + ucode[offset++] = (b3 << 4) | 0x02 | (i >> 6); + ucode[offset++] = (i << 2) | 0x03; + ucode[offset++] = b2; + } + + // ctx_arb[kill] + ucode[offset++] = 0xe0; + ucode[offset++] = 0x00; + ucode[offset++] = 0x01; + ucode[offset++] = 0x00; + ucode[offset++] = 0x00; +} + +static int set_initial_registers(int uengine, struct ixp2000_uengine_code *c) +{ + int per_ctx_regs; + u32 *gpr_a; + u32 *gpr_b; + u8 *ucode; + int i; + + gpr_a = kmalloc(128 * sizeof(u32), GFP_KERNEL); + gpr_b = kmalloc(128 * sizeof(u32), GFP_KERNEL); + ucode = kmalloc(513 * 5, GFP_KERNEL); + if (gpr_a == NULL || gpr_b == NULL || ucode == NULL) { + kfree(ucode); + kfree(gpr_b); + kfree(gpr_a); + return 1; + } + + per_ctx_regs = 16; + if (c->uengine_parameters & IXP2000_UENGINE_4_CONTEXTS) + per_ctx_regs = 32; + + memset(gpr_a, 0, sizeof(gpr_a)); + memset(gpr_b, 0, sizeof(gpr_b)); + for (i = 0; i < 256; i++) { + struct ixp2000_reg_value *r = c->initial_reg_values + i; + u32 *bank; + int inc; + int j; + + if (r->reg == -1) + break; + + bank = (r->reg & 0x400) ? gpr_b : gpr_a; + inc = (r->reg & 0x80) ? 128 : per_ctx_regs; + + j = r->reg & 0x7f; + while (j < 128) { + bank[j] = r->value; + j += inc; + } + } + + generate_ucode(ucode, gpr_a, gpr_b); + ixp2000_uengine_load_microcode(uengine, ucode, 513); + ixp2000_uengine_init_context(uengine, 0, 0); + ixp2000_uengine_start_contexts(uengine, 0x01); + for (i = 0; i < 100; i++) { + u32 status; + + status = ixp2000_uengine_csr_read(uengine, ACTIVE_CTX_STS); + if (!(status & 0x80000000)) + break; + } + ixp2000_uengine_stop_contexts(uengine, 0x01); + + kfree(ucode); + kfree(gpr_b); + kfree(gpr_a); + + return !!(i == 100); +} + +int ixp2000_uengine_load(int uengine, struct ixp2000_uengine_code *c) +{ + int ctx; + + if (!check_ixp_type(c)) + return 1; + + if (!(ixp2000_uengine_mask & (1 << uengine))) + return 1; + + ixp2000_uengine_reset(1 << uengine); + ixp2000_uengine_set_mode(uengine, c->uengine_parameters); + if (set_initial_registers(uengine, c)) + return 1; + ixp2000_uengine_load_microcode(uengine, c->insns, c->num_insns); + + for (ctx = 0; ctx < 8; ctx++) + ixp2000_uengine_init_context(uengine, ctx, 0); + + return 0; +} +EXPORT_SYMBOL(ixp2000_uengine_load); + + +static int __init ixp2000_uengine_init(void) +{ + int uengine; + u32 value; + + /* + * Determine number of microengines present. + */ + switch ((ixp2000_reg_read(IXP2000_PRODUCT_ID) >> 8) & 0x1fff) { + case 0: /* IXP2800 */ + case 1: /* IXP2850 */ + ixp2000_uengine_mask = 0x00ff00ff; + break; + + case 2: /* IXP2400 */ + ixp2000_uengine_mask = 0x000f000f; + break; + + default: + printk(KERN_INFO "Detected unknown IXP2000 model (%.8x)\n", + (unsigned int)ixp2000_reg_read(IXP2000_PRODUCT_ID)); + ixp2000_uengine_mask = 0x00000000; + break; + } + + /* + * Reset microengines. + */ + ixp2000_reg_write(IXP2000_RESET1, ixp2000_uengine_mask); + ixp2000_reg_write(IXP2000_RESET1, 0); + + /* + * Synchronise timestamp counters across all microengines. + */ + value = ixp2000_reg_read(IXP2000_MISC_CONTROL); + ixp2000_reg_write(IXP2000_MISC_CONTROL, value & ~0x80); + for (uengine = 0; uengine < 32; uengine++) { + if (ixp2000_uengine_mask & (1 << uengine)) { + ixp2000_uengine_csr_write(uengine, TIMESTAMP_LOW, 0); + ixp2000_uengine_csr_write(uengine, TIMESTAMP_HIGH, 0); + } + } + ixp2000_reg_write(IXP2000_MISC_CONTROL, value | 0x80); + + return 0; +} + +subsys_initcall(ixp2000_uengine_init); |