arch/powerpc/sysdev/cpm_common.c

   1 /*
   2  * Common CPM code
   3  *
   4  * Author: Scott Wood <scottwood@freescale.com>
   5  *
   6  * Copyright 2007 Freescale Semiconductor, Inc.
   7  *
   8  * Some parts derived from commproc.c/cpm2_common.c, which is:
   9  * Copyright (c) 1997 Dan error_act (dmalek@jlc.net)
  10  * Copyright (c) 1999-2001 Dan Malek <dan@embeddedalley.com>
  11  * Copyright (c) 2000 MontaVista Software, Inc (source@mvista.com)
  12  * 2006 (c) MontaVista Software, Inc.
  13  * Vitaly Bordug <vbordug@ru.mvista.com>
  14  *
  15  * This program is free software; you can redistribute it and/or modify
  16  * it under the terms of version 2 of the GNU General Public License as
  17  * published by the Free Software Foundation.
  18  */
  19
  20 #include <linux/init.h>
  21 #include <linux/of_device.h>
  22
  23 #include <asm/udbg.h>
  24 #include <asm/io.h>
  25 #include <asm/system.h>
  26 #include <asm/rheap.h>
  27 #include <asm/cpm.h>
  28
  29 #include <mm/mmu_decl.h>
  30
  31 #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
  32 static u32 __iomem *cpm_udbg_txdesc =
  33         (u32 __iomem __force *)CONFIG_PPC_EARLY_DEBUG_CPM_ADDR;
  34
  35 static void udbg_putc_cpm(char c)
  36 {
  37         u8 __iomem *txbuf = (u8 __iomem __force *)in_be32(&cpm_udbg_txdesc[1]);
  38
  39         if (c == '\n')
  40                 udbg_putc('\r');
  41
  42         while (in_be32(&cpm_udbg_txdesc[0]) & 0x80000000)
  43                 ;
  44
  45         out_8(txbuf, c);
  46         out_be32(&cpm_udbg_txdesc[0], 0xa0000001);
  47 }
  48
  49 void __init udbg_init_cpm(void)
  50 {
  51         if (cpm_udbg_txdesc) {
  52 #ifdef CONFIG_CPM2
  53                 setbat(1, 0xf0000000, 0xf0000000, 1024*1024, _PAGE_IO);
  54 #endif
  55                 udbg_putc = udbg_putc_cpm;
  56                 udbg_putc('X');
  57         }
  58 }
  59 #endif
  60
  61 static spinlock_t cpm_muram_lock;
  62 static rh_block_t cpm_boot_muram_rh_block[16];
  63 static rh_info_t cpm_muram_info;
  64 static u8 __iomem *muram_vbase;
  65 static phys_addr_t muram_pbase;
  66
  67 /* Max address size we deal with */
  68 #define OF_MAX_ADDR_CELLS       4
  69
  70 int __init cpm_muram_init(void)
  71 {
  72         struct device_node *np;
  73         struct resource r;
  74         u32 zero[OF_MAX_ADDR_CELLS] = {};
  75         resource_size_t max = 0;
  76         int i = 0;
  77         int ret = 0;
  78
  79         spin_lock_init(&cpm_muram_lock);
  80         /* initialize the info header */
  81         rh_init(&cpm_muram_info, 1,
  82                 sizeof(cpm_boot_muram_rh_block) /
  83                 sizeof(cpm_boot_muram_rh_block[0]),
  84                 cpm_boot_muram_rh_block);
  85
  86         np = of_find_compatible_node(NULL, NULL, "fsl,cpm-muram-data");
  87         if (!np) {
  88                 printk(KERN_ERR "Cannot find CPM muram data node");
  89                 ret = -ENODEV;
  90                 goto out;
  91         }
  92
  93         muram_pbase = of_translate_address(np, zero);
  94         if (muram_pbase == (phys_addr_t)OF_BAD_ADDR) {
  95                 printk(KERN_ERR "Cannot translate zero through CPM muram node");
  96                 ret = -ENODEV;
  97                 goto out;
  98         }
  99
 100         while (of_address_to_resource(np, i++, &r) == 0) {
 101                 if (r.end > max)
 102                         max = r.end;
 103
 104                 rh_attach_region(&cpm_muram_info, r.start - muram_pbase,
 105                                  r.end - r.start + 1);
 106         }
 107
 108         muram_vbase = ioremap(muram_pbase, max - muram_pbase + 1);
 109         if (!muram_vbase) {
 110                 printk(KERN_ERR "Cannot map CPM muram");
 111                 ret = -ENOMEM;
 112         }
 113
 114 out:
 115         of_node_put(np);
 116         return ret;
 117 }
 118
 119 /**
 120  * cpm_muram_alloc - allocate the requested size worth of multi-user ram
 121  * @size: number of bytes to allocate
 122  * @align: requested alignment, in bytes
 123  *
 124  * This function returns an offset into the muram area.
 125  * Use cpm_dpram_addr() to get the virtual address of the area.
 126  * Use cpm_muram_free() to free the allocation.
 127  */
 128 unsigned long cpm_muram_alloc(unsigned long size, unsigned long align)
 129 {
 130         unsigned long start;
 131         unsigned long flags;
 132
 133         spin_lock_irqsave(&cpm_muram_lock, flags);
 134         cpm_muram_info.alignment = align;
 135         start = rh_alloc(&cpm_muram_info, size, "commproc");
 136         spin_unlock_irqrestore(&cpm_muram_lock, flags);
 137
 138         return start;
 139 }
 140 EXPORT_SYMBOL(cpm_muram_alloc);
 141
 142 /**
 143  * cpm_muram_free - free a chunk of multi-user ram
 144  * @offset: The beginning of the chunk as returned by cpm_muram_alloc().
 145  */
 146 int cpm_muram_free(unsigned long offset)
 147 {
 148         int ret;
 149         unsigned long flags;
 150
 151         spin_lock_irqsave(&cpm_muram_lock, flags);
 152         ret = rh_free(&cpm_muram_info, offset);
 153         spin_unlock_irqrestore(&cpm_muram_lock, flags);
 154
 155         return ret;
 156 }
 157 EXPORT_SYMBOL(cpm_muram_free);
 158
 159 /**
 160  * cpm_muram_alloc_fixed - reserve a specific region of multi-user ram
 161  * @offset: the offset into the muram area to reserve
 162  * @size: the number of bytes to reserve
 163  *
 164  * This function returns "start" on success, -ENOMEM on failure.
 165  * Use cpm_dpram_addr() to get the virtual address of the area.
 166  * Use cpm_muram_free() to free the allocation.
 167  */
 168 unsigned long cpm_muram_alloc_fixed(unsigned long offset, unsigned long size)
 169 {
 170         unsigned long start;
 171         unsigned long flags;
 172
 173         spin_lock_irqsave(&cpm_muram_lock, flags);
 174         cpm_muram_info.alignment = 1;
 175         start = rh_alloc_fixed(&cpm_muram_info, offset, size, "commproc");
 176         spin_unlock_irqrestore(&cpm_muram_lock, flags);
 177
 178         return start;
 179 }
 180 EXPORT_SYMBOL(cpm_muram_alloc_fixed);
 181
 182 /**
 183  * cpm_muram_addr - turn a muram offset into a virtual address
 184  * @offset: muram offset to convert
 185  */
 186 void __iomem *cpm_muram_addr(unsigned long offset)
 187 {
 188         return muram_vbase + offset;
 189 }
 190 EXPORT_SYMBOL(cpm_muram_addr);
 191
 192 /**
 193  * cpm_muram_dma - turn a muram virtual address into a DMA address
 194  * @offset: virtual address from cpm_muram_addr() to convert
 195  */
 196 dma_addr_t cpm_muram_dma(void __iomem *addr)
 197 {
 198         return muram_pbase + ((u8 __iomem *)addr - muram_vbase);
 199 }
 200 EXPORT_SYMBOL(cpm_muram_dma);