path: root/arch/alpha/kernel/core_lca.c

// SPDX-License-Identifier: GPL-2.0
/*
 *	linux/arch/alpha/kernel/core_lca.c
 *
 * Written by David Mosberger (davidm@cs.arizona.edu) with some code
 * taken from Dave Rusling's (david.rusling@reo.mts.dec.com) 32-bit
 * bios code.
 *
 * Code common to all LCA core logic chips.
 */

#define __EXTERN_INLINE inline
#include <asm/io.h>
#include <asm/core_lca.h>
#undef __EXTERN_INLINE

#include <linux/types.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/tty.h>

#include <asm/ptrace.h>
#include <asm/irq_regs.h>
#include <asm/smp.h>

#include "proto.h"
#include "pci_impl.h"


/*
 * BIOS32-style PCI interface:
 */

/*
 * Machine check reasons.  Defined according to PALcode sources
 * (osf.h and platform.h).
 */
#define MCHK_K_TPERR		0x0080
#define MCHK_K_TCPERR		0x0082
#define MCHK_K_HERR		0x0084
#define MCHK_K_ECC_C		0x0086
#define MCHK_K_ECC_NC		0x0088
#define MCHK_K_UNKNOWN		0x008A
#define MCHK_K_CACKSOFT		0x008C
#define MCHK_K_BUGCHECK		0x008E
#define MCHK_K_OS_BUGCHECK	0x0090
#define MCHK_K_DCPERR		0x0092
#define MCHK_K_ICPERR		0x0094


/*
 * Platform-specific machine-check reasons:
 */
#define MCHK_K_SIO_SERR		0x204	/* all platforms so far */
#define MCHK_K_SIO_IOCHK	0x206	/* all platforms so far */
#define MCHK_K_DCSR		0x208	/* all but Noname */


/*
 * Given a bus, device, and function number, compute resulting
 * configuration space address and setup the LCA_IOC_CONF register
 * accordingly.  It is therefore not safe to have concurrent
 * invocations to configuration space access routines, but there
 * really shouldn't be any need for this.
 *
 * Type 0:
 *
 *  3 3|3 3 2 2|2 2 2 2|2 2 2 2|1 1 1 1|1 1 1 1|1 1 
 *  3 2|1 0 9 8|7 6 5 4|3 2 1 0|9 8 7 6|5 4 3 2|1 0 9 8|7 6 5 4|3 2 1 0
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * | | | | | | | | | | | | | | | | | | | | | | | |F|F|F|R|R|R|R|R|R|0|0|
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *	31:11	Device select bit.
 * 	10:8	Function number
 * 	 7:2	Register number
 *
 * Type 1:
 *
 *  3 3|3 3 2 2|2 2 2 2|2 2 2 2|1 1 1 1|1 1 1 1|1 1 
 *  3 2|1 0 9 8|7 6 5 4|3 2 1 0|9 8 7 6|5 4 3 2|1 0 9 8|7 6 5 4|3 2 1 0
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * | | | | | | | | | | |B|B|B|B|B|B|B|B|D|D|D|D|D|F|F|F|R|R|R|R|R|R|0|1|
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *	31:24	reserved
 *	23:16	bus number (8 bits = 128 possible buses)
 *	15:11	Device number (5 bits)
 *	10:8	function number
 *	 7:2	register number
 *  
 * Notes:
 *	The function number selects which function of a multi-function device 
 *	(e.g., SCSI and Ethernet).
 * 
 *	The register selects a DWORD (32 bit) register offset.  Hence it
 *	doesn't get shifted by 2 bits as we want to "drop" the bottom two
 *	bits.
 */

static int
mk_conf_addr(struct pci_bus *pbus, unsigned int device_fn, int where,
	     unsigned long *pci_addr)
{
	unsigned long addr;
	u8 bus = pbus->number;

	if (bus == 0) {
		int device = device_fn >> 3;
		int func = device_fn & 0x7;

		/* Type 0 configuration cycle.  */

		if (device > 12) {
			return -1;
		}

		*(vulp)LCA_IOC_CONF = 0;
		addr = (1 << (11 + device)) | (func << 8) | where;
	} else {
		/* Type 1 configuration cycle.  */
		*(vulp)LCA_IOC_CONF = 1;
		addr = (bus << 16) | (device_fn << 8) | where;
	}
	*pci_addr = addr;
	return 0;
}

static unsigned int
conf_read(unsigned long addr)
{
	unsigned long flags, code, stat0;
	unsigned int value;

	local_irq_save(flags);

	/* Reset status register to avoid losing errors.  */
	stat0 = *(vulp)LCA_IOC_STAT0;
	*(vulp)LCA_IOC_STAT0 = stat0;
	mb();

	/* Access configuration space.  */
	value = *(vuip)addr;
	draina();

	stat0 = *(vulp)LCA_IOC_STAT0;
	if (stat0 & LCA_IOC_STAT0_ERR) {
		code = ((stat0 >> LCA_IOC_STAT0_CODE_SHIFT)
			& LCA_IOC_STAT0_CODE_MASK);
		if (code != 1) {
			printk("lca.c:conf_read: got stat0=%lx\n", stat0);
		}

		/* Reset error status.  */
		*(vulp)LCA_IOC_STAT0 = stat0;
		mb();

		/* Reset machine check.  */
		wrmces(0x7);

		value = 0xffffffff;
	}
	local_irq_restore(flags);
	return value;
}

static void
conf_write(unsigned long addr, unsigned int value)
{
	unsigned long flags, code, stat0;

	local_irq_save(flags);	/* avoid getting hit by machine check */

	/* Reset status register to avoid losing errors.  */
	stat0 = *(vulp)LCA_IOC_STAT0;
	*(vulp)LCA_IOC_STAT0 = stat0;
	mb();

	/* Access configuration space.  */
	*(vuip)addr = value;
	draina();

	stat0 = *(vulp)LCA_IOC_STAT0;
	if (stat0 & LCA_IOC_STAT0_ERR) {
		code = ((stat0 >> LCA_IOC_STAT0_CODE_SHIFT)
			& LCA_IOC_STAT0_CODE_MASK);
		if (code != 1) {
			printk("lca.c:conf_write: got stat0=%lx\n", stat0);
		}

		/* Reset error status.  */
		*(vulp)LCA_IOC_STAT0 = stat0;
		mb();

		/* Reset machine check. */
		wrmces(0x7);
	}
	local_irq_restore(flags);
}

static int
lca_read_config(struct pci_bus *bus, unsigned int devfn, int where,
		int size, u32 *value)
{
	unsigned long addr, pci_addr;
	long mask;
	int shift;

	if (mk_conf_addr(bus, devfn, where, &pci_addr))
		return PCIBIOS_DEVICE_NOT_FOUND;

	shift = (where & 3) * 8;
	mask = (size - 1) * 8;
	addr = (pci_addr << 5) + mask + LCA_CONF;
	*value = conf_read(addr) >> (shift);
	return PCIBIOS_SUCCESSFUL;
}

static int 
lca_write_config(struct pci_bus *bus, unsigned int devfn, int where, int size,
		 u32 value)
{
	unsigned long addr, pci_addr;
	long mask;

	if (mk_conf_addr(bus, devfn, where, &pci_addr))
		return PCIBIOS_DEVICE_NOT_FOUND;

	mask = (size - 1) * 8;
	addr = (pci_addr << 5) + mask + LCA_CONF;
	conf_write(addr, value << ((where & 3) * 8));
	return PCIBIOS_SUCCESSFUL;
}

struct pci_ops lca_pci_ops = 
{
	.read =		lca_read_config,
	.write =	lca_write_config,
};

void
lca_pci_tbi(struct pci_controller *hose, dma_addr_t start, dma_addr_t end)
{
	wmb();
	*(vulp)LCA_IOC_TBIA = 0;
	mb();
}

void __init
lca_init_arch(void)
{
	struct pci_controller *hose;

	/*
	 * Create our single hose.
	 */

	pci_isa_hose = hose = alloc_pci_controller();
	hose->io_space = &ioport_resource;
	hose->mem_space = &iomem_resource;
	hose->index = 0;

	hose->sparse_mem_base = LCA_SPARSE_MEM - IDENT_ADDR;
	hose->dense_mem_base = LCA_DENSE_MEM - IDENT_ADDR;
	hose->sparse_io_base = LCA_IO - IDENT_ADDR;
	hose->dense_io_base = 0;

	/*
	 * Set up the PCI to main memory translation windows.
	 *
	 * Mimic the SRM settings for the direct-map window.
	 *   Window 0 is scatter-gather 8MB at 8MB (for isa).
	 *   Window 1 is direct access 1GB at 1GB.
	 *
	 * Note that we do not try to save any of the DMA window CSRs
	 * before setting them, since we cannot read those CSRs on LCA.
	 */
	hose->sg_isa = iommu_arena_new(hose, 0x00800000, 0x00800000,
				       SMP_CACHE_BYTES);
	hose->sg_pci = NULL;
	__direct_map_base = 0x40000000;
	__direct_map_size = 0x40000000;

	*(vulp)LCA_IOC_W_BASE0 = hose->sg_isa->dma_base | (3UL << 32);
	*(vulp)LCA_IOC_W_MASK0 = (hose->sg_isa->size - 1) & 0xfff00000;
	*(vulp)LCA_IOC_T_BASE0 = virt_to_phys(hose->sg_isa->ptes);

	*(vulp)LCA_IOC_W_BASE1 = __direct_map_base | (2UL << 32);
	*(vulp)LCA_IOC_W_MASK1 = (__direct_map_size - 1) & 0xfff00000;
	*(vulp)LCA_IOC_T_BASE1 = 0;

	*(vulp)LCA_IOC_TB_ENA = 0x80;

	lca_pci_tbi(hose, 0, -1);

	/*
	 * Disable PCI parity for now.  The NCR53c810 chip has
	 * troubles meeting the PCI spec which results in
	 * data parity errors.
	 */
	*(