265 lines
9.0 KiB
C
265 lines
9.0 KiB
C
/*
|
|
* linux/arch/cris/arch-v10/mm/init.c
|
|
*
|
|
*/
|
|
#include <linux/config.h>
|
|
#include <linux/mmzone.h>
|
|
#include <linux/init.h>
|
|
#include <linux/bootmem.h>
|
|
#include <linux/mm.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/page.h>
|
|
#include <asm/types.h>
|
|
#include <asm/mmu.h>
|
|
#include <asm/io.h>
|
|
#include <asm/mmu_context.h>
|
|
#include <asm/arch/svinto.h>
|
|
|
|
extern void tlb_init(void);
|
|
|
|
/*
|
|
* The kernel is already mapped with a kernel segment at kseg_c so
|
|
* we don't need to map it with a page table. However head.S also
|
|
* temporarily mapped it at kseg_4 so we should set up the ksegs again,
|
|
* clear the TLB and do some other paging setup stuff.
|
|
*/
|
|
|
|
void __init
|
|
paging_init(void)
|
|
{
|
|
int i;
|
|
unsigned long zones_size[MAX_NR_ZONES];
|
|
|
|
printk("Setting up paging and the MMU.\n");
|
|
|
|
/* clear out the init_mm.pgd that will contain the kernel's mappings */
|
|
|
|
for(i = 0; i < PTRS_PER_PGD; i++)
|
|
swapper_pg_dir[i] = __pgd(0);
|
|
|
|
/* make sure the current pgd table points to something sane
|
|
* (even if it is most probably not used until the next
|
|
* switch_mm)
|
|
*/
|
|
|
|
per_cpu(current_pgd, smp_processor_id()) = init_mm.pgd;
|
|
|
|
/* initialise the TLB (tlb.c) */
|
|
|
|
tlb_init();
|
|
|
|
/* see README.mm for details on the KSEG setup */
|
|
|
|
#ifdef CONFIG_CRIS_LOW_MAP
|
|
/* Etrax-100 LX version 1 has a bug so that we cannot map anything
|
|
* across the 0x80000000 boundary, so we need to shrink the user-virtual
|
|
* area to 0x50000000 instead of 0xb0000000 and map things slightly
|
|
* different. The unused areas are marked as paged so that we can catch
|
|
* freak kernel accesses there.
|
|
*
|
|
* The ARTPEC chip is mapped at 0xa so we pass that segment straight
|
|
* through. We cannot vremap it because the vmalloc area is below 0x8
|
|
* and Juliette needs an uncached area above 0x8.
|
|
*
|
|
* Same thing with 0xc and 0x9, which is memory-mapped I/O on some boards.
|
|
* We map them straight over in LOW_MAP, but use vremap in LX version 2.
|
|
*/
|
|
|
|
#define CACHED_BOOTROM (KSEG_F | 0x08000000UL)
|
|
|
|
*R_MMU_KSEG = ( IO_STATE(R_MMU_KSEG, seg_f, seg ) | /* bootrom */
|
|
IO_STATE(R_MMU_KSEG, seg_e, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_d, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_c, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_b, seg ) | /* kernel reg area */
|
|
#ifdef CONFIG_JULIETTE
|
|
IO_STATE(R_MMU_KSEG, seg_a, seg ) | /* ARTPEC etc. */
|
|
#else
|
|
IO_STATE(R_MMU_KSEG, seg_a, page ) |
|
|
#endif
|
|
IO_STATE(R_MMU_KSEG, seg_9, seg ) | /* LED's on some boards */
|
|
IO_STATE(R_MMU_KSEG, seg_8, seg ) | /* CSE0/1, flash and I/O */
|
|
IO_STATE(R_MMU_KSEG, seg_7, page ) | /* kernel vmalloc area */
|
|
IO_STATE(R_MMU_KSEG, seg_6, seg ) | /* kernel DRAM area */
|
|
IO_STATE(R_MMU_KSEG, seg_5, seg ) | /* cached flash */
|
|
IO_STATE(R_MMU_KSEG, seg_4, page ) | /* user area */
|
|
IO_STATE(R_MMU_KSEG, seg_3, page ) | /* user area */
|
|
IO_STATE(R_MMU_KSEG, seg_2, page ) | /* user area */
|
|
IO_STATE(R_MMU_KSEG, seg_1, page ) | /* user area */
|
|
IO_STATE(R_MMU_KSEG, seg_0, page ) ); /* user area */
|
|
|
|
*R_MMU_KBASE_HI = ( IO_FIELD(R_MMU_KBASE_HI, base_f, 0x3 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_e, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_d, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_c, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_b, 0xb ) |
|
|
#ifdef CONFIG_JULIETTE
|
|
IO_FIELD(R_MMU_KBASE_HI, base_a, 0xa ) |
|
|
#else
|
|
IO_FIELD(R_MMU_KBASE_HI, base_a, 0x0 ) |
|
|
#endif
|
|
IO_FIELD(R_MMU_KBASE_HI, base_9, 0x9 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_8, 0x8 ) );
|
|
|
|
*R_MMU_KBASE_LO = ( IO_FIELD(R_MMU_KBASE_LO, base_7, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_6, 0x4 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_5, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_4, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_3, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_2, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_1, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_0, 0x0 ) );
|
|
#else
|
|
/* This code is for the corrected Etrax-100 LX version 2... */
|
|
|
|
#define CACHED_BOOTROM (KSEG_A | 0x08000000UL)
|
|
|
|
*R_MMU_KSEG = ( IO_STATE(R_MMU_KSEG, seg_f, seg ) | /* cached flash */
|
|
IO_STATE(R_MMU_KSEG, seg_e, seg ) | /* uncached flash */
|
|
IO_STATE(R_MMU_KSEG, seg_d, page ) | /* vmalloc area */
|
|
IO_STATE(R_MMU_KSEG, seg_c, seg ) | /* kernel area */
|
|
IO_STATE(R_MMU_KSEG, seg_b, seg ) | /* kernel reg area */
|
|
IO_STATE(R_MMU_KSEG, seg_a, seg ) | /* bootrom */
|
|
IO_STATE(R_MMU_KSEG, seg_9, page ) | /* user area */
|
|
IO_STATE(R_MMU_KSEG, seg_8, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_7, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_6, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_5, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_4, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_3, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_2, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_1, page ) |
|
|
IO_STATE(R_MMU_KSEG, seg_0, page ) );
|
|
|
|
*R_MMU_KBASE_HI = ( IO_FIELD(R_MMU_KBASE_HI, base_f, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_e, 0x8 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_d, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_c, 0x4 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_b, 0xb ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_a, 0x3 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_9, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_HI, base_8, 0x0 ) );
|
|
|
|
*R_MMU_KBASE_LO = ( IO_FIELD(R_MMU_KBASE_LO, base_7, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_6, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_5, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_4, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_3, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_2, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_1, 0x0 ) |
|
|
IO_FIELD(R_MMU_KBASE_LO, base_0, 0x0 ) );
|
|
#endif
|
|
|
|
*R_MMU_CONTEXT = ( IO_FIELD(R_MMU_CONTEXT, page_id, 0 ) );
|
|
|
|
/* The MMU has been enabled ever since head.S but just to make
|
|
* it totally obvious we do it here as well.
|
|
*/
|
|
|
|
*R_MMU_CTRL = ( IO_STATE(R_MMU_CTRL, inv_excp, enable ) |
|
|
IO_STATE(R_MMU_CTRL, acc_excp, enable ) |
|
|
IO_STATE(R_MMU_CTRL, we_excp, enable ) );
|
|
|
|
*R_MMU_ENABLE = IO_STATE(R_MMU_ENABLE, mmu_enable, enable);
|
|
|
|
/*
|
|
* initialize the bad page table and bad page to point
|
|
* to a couple of allocated pages
|
|
*/
|
|
|
|
empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
|
|
memset((void *)empty_zero_page, 0, PAGE_SIZE);
|
|
|
|
/* All pages are DMA'able in Etrax, so put all in the DMA'able zone */
|
|
|
|
zones_size[0] = ((unsigned long)high_memory - PAGE_OFFSET) >> PAGE_SHIFT;
|
|
|
|
for (i = 1; i < MAX_NR_ZONES; i++)
|
|
zones_size[i] = 0;
|
|
|
|
/* Use free_area_init_node instead of free_area_init, because the former
|
|
* is designed for systems where the DRAM starts at an address substantially
|
|
* higher than 0, like us (we start at PAGE_OFFSET). This saves space in the
|
|
* mem_map page array.
|
|
*/
|
|
|
|
free_area_init_node(0, &contig_page_data, zones_size, PAGE_OFFSET >> PAGE_SHIFT, 0);
|
|
}
|
|
|
|
/* Initialize remaps of some I/O-ports. It is important that this
|
|
* is called before any driver is initialized.
|
|
*/
|
|
|
|
static int
|
|
__init init_ioremap(void)
|
|
{
|
|
|
|
/* Give the external I/O-port addresses their values */
|
|
|
|
#ifdef CONFIG_CRIS_LOW_MAP
|
|
/* Simply a linear map (see the KSEG map above in paging_init) */
|
|
port_cse1_addr = (volatile unsigned long *)(MEM_CSE1_START |
|
|
MEM_NON_CACHEABLE);
|
|
port_csp0_addr = (volatile unsigned long *)(MEM_CSP0_START |
|
|
MEM_NON_CACHEABLE);
|
|
port_csp4_addr = (volatile unsigned long *)(MEM_CSP4_START |
|
|
MEM_NON_CACHEABLE);
|
|
#else
|
|
/* Note that nothing blows up just because we do this remapping
|
|
* it's ok even if the ports are not used or connected
|
|
* to anything (or connected to a non-I/O thing) */
|
|
port_cse1_addr = (volatile unsigned long *)
|
|
ioremap((unsigned long)(MEM_CSE1_START | MEM_NON_CACHEABLE), 16);
|
|
port_csp0_addr = (volatile unsigned long *)
|
|
ioremap((unsigned long)(MEM_CSP0_START | MEM_NON_CACHEABLE), 16);
|
|
port_csp4_addr = (volatile unsigned long *)
|
|
ioremap((unsigned long)(MEM_CSP4_START | MEM_NON_CACHEABLE), 16);
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
__initcall(init_ioremap);
|
|
|
|
/* Helper function for the two below */
|
|
|
|
static inline void
|
|
flush_etrax_cacherange(void *startadr, int length)
|
|
{
|
|
/* CACHED_BOOTROM is mapped to the boot-rom area (cached) which
|
|
* we can use to get fast dummy-reads of cachelines
|
|
*/
|
|
|
|
volatile short *flushadr = (volatile short *)(((unsigned long)startadr & ~PAGE_MASK) |
|
|
CACHED_BOOTROM);
|
|
|
|
length = length > 8192 ? 8192 : length; /* No need to flush more than cache size */
|
|
|
|
while(length > 0) {
|
|
*flushadr; /* dummy read to flush */
|
|
flushadr += (32/sizeof(short)); /* a cacheline is 32 bytes */
|
|
length -= 32;
|
|
}
|
|
}
|
|
|
|
/* Due to a bug in Etrax100(LX) all versions, receiving DMA buffers
|
|
* will occationally corrupt certain CPU writes if the DMA buffers
|
|
* happen to be hot in the cache.
|
|
*
|
|
* As a workaround, we have to flush the relevant parts of the cache
|
|
* before (re) inserting any receiving descriptor into the DMA HW.
|
|
*/
|
|
|
|
void
|
|
prepare_rx_descriptor(struct etrax_dma_descr *desc)
|
|
{
|
|
flush_etrax_cacherange((void *)desc->buf, desc->sw_len ? desc->sw_len : 65536);
|
|
}
|
|
|
|
/* Do the same thing but flush the entire cache */
|
|
|
|
void
|
|
flush_etrax_cache(void)
|
|
{
|
|
flush_etrax_cacherange(0, 8192);
|
|
}
|