arch/mips/alchemy/devboards/bcsr.c

   1 /*
   2  * bcsr.h -- Db1xxx/Pb1xxx Devboard CPLD registers ("BCSR") abstraction.
   3  *
   4  * All Alchemy development boards (except, of course, the weird PB1000)
   5  * have a few registers in a CPLD with standardised layout; they mostly
   6  * only differ in base address.
   7  * All registers are 16bits wide with 32bit spacing.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/spinlock.h>
  12 #include <asm/addrspace.h>
  13 #include <asm/io.h>
  14 #include <asm/mach-db1x00/bcsr.h>
  15
  16 static struct bcsr_reg {
  17         void __iomem *raddr;
  18         spinlock_t lock;
  19 } bcsr_regs[BCSR_CNT];
  20
  21 void __init bcsr_init(unsigned long bcsr1_phys, unsigned long bcsr2_phys)
  22 {
  23         int i;
  24
  25         bcsr1_phys = KSEG1ADDR(CPHYSADDR(bcsr1_phys));
  26         bcsr2_phys = KSEG1ADDR(CPHYSADDR(bcsr2_phys));
  27
  28         for (i = 0; i < BCSR_CNT; i++) {
  29                 if (i >= BCSR_HEXLEDS)
  30                         bcsr_regs[i].raddr = (void __iomem *)bcsr2_phys +
  31                                         (0x04 * (i - BCSR_HEXLEDS));
  32                 else
  33                         bcsr_regs[i].raddr = (void __iomem *)bcsr1_phys +
  34                                         (0x04 * i);
  35
  36                 spin_lock_init(&bcsr_regs[i].lock);
  37         }
  38 }
  39
  40 unsigned short bcsr_read(enum bcsr_id reg)
  41 {
  42         unsigned short r;
  43         unsigned long flags;
  44
  45         spin_lock_irqsave(&bcsr_regs[reg].lock, flags);
  46         r = __raw_readw(bcsr_regs[reg].raddr);
  47         spin_unlock_irqrestore(&bcsr_regs[reg].lock, flags);
  48         return r;
  49 }
  50 EXPORT_SYMBOL_GPL(bcsr_read);
  51
  52 void bcsr_write(enum bcsr_id reg, unsigned short val)
  53 {
  54         unsigned long flags;
  55
  56         spin_lock_irqsave(&bcsr_regs[reg].lock, flags);
  57         __raw_writew(val, bcsr_regs[reg].raddr);
  58         wmb();
  59         spin_unlock_irqrestore(&bcsr_regs[reg].lock, flags);
  60 }
  61 EXPORT_SYMBOL_GPL(bcsr_write);
  62
  63 void bcsr_mod(enum bcsr_id reg, unsigned short clr, unsigned short set)
  64 {
  65         unsigned short r;
  66         unsigned long flags;
  67
  68         spin_lock_irqsave(&bcsr_regs[reg].lock, flags);
  69         r = __raw_readw(bcsr_regs[reg].raddr);
  70         r &= ~clr;
  71         r |= set;
  72         __raw_writew(r, bcsr_regs[reg].raddr);
  73         wmb();
  74         spin_unlock_irqrestore(&bcsr_regs[reg].lock, flags);
  75 }
  76 EXPORT_SYMBOL_GPL(bcsr_mod);