/*
* Access to HP-HIL MLC through HP System Device Controller.
*
* Copyright (c) 2001 Brian S. Julin
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL").
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
*
* References:
* HP-HIL Technical Reference Manual. Hewlett Packard Product No. 45918A
* System Device Controller Microprocessor Firmware Theory of Operation
* for Part Number 1820-4784 Revision B. Dwg No. A-1820-4784-2
*
*/
#include <linux/hil_mlc.h>
#include <linux/hp_sdc.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/string.h>
#include <asm/semaphore.h>
#define PREFIX "HP SDC MLC: "
static hil_mlc hp_sdc_mlc;
MODULE_AUTHOR("Brian S. Julin <bri@calyx.com>");
MODULE_DESCRIPTION("Glue for onboard HIL MLC in HP-PARISC machines");
MODULE_LICENSE("Dual BSD/GPL");
struct hp_sdc_mlc_priv_s {
int emtestmode;
hp_sdc_transaction trans;
u8 tseq[16];
int got5x;
} hp_sdc_mlc_priv;
/************************* Interrupt context ******************************/
static void hp_sdc_mlc_isr (int irq, void *dev_id,
uint8_t status, uint8_t data) {
int idx;
hil_mlc *mlc = &hp_sdc_mlc;
write_lock(&(mlc->lock));
if (mlc->icount < 0) {
printk(KERN_WARNING PREFIX "HIL Overflow!\n");
up(&mlc->isem);
goto out;
}
idx = 15 - mlc->icount;
if ((status & HP_SDC_STATUS_IRQMASK) == HP_SDC_STATUS_HILDATA) {
mlc->ipacket[idx] |= data | HIL_ERR_INT;
mlc->icount--;
if (hp_sdc_mlc_priv.got5x) goto check;
if (!idx) goto check;
if ((mlc->ipacket[idx-1] & HIL_PKT_ADDR_MASK) !=
(mlc->ipacket[idx] & HIL_PKT_ADDR_MASK)) {
mlc->ipacket[idx] &= ~HIL_PKT_ADDR_MASK;
mlc->ipacket[idx] |= (mlc->ipacket[idx-1]
& HIL_PKT_ADDR_MASK);
}
goto check;
}
/* We know status is 5X */
if (data & HP_SDC_HIL_ISERR) goto err;
mlc->ipacket[idx] =
(data & HP_SDC_HIL_R1MASK) << HIL_PKT_ADDR_SHIFT;
hp_sdc_mlc_priv.got5x = 1;
goto out;
check:
hp_sdc_mlc_priv.got5x = 0;
if (mlc->imatch == 0) goto done;
if ((mlc->imatch == (HIL_ERR_INT | HIL_PKT_CMD | HIL_CMD_POL))
&& (mlc->ipacket[idx] == (mlc->imatch | idx))) goto done;
if (mlc->ipacket[idx] == mlc->imatch) goto done;
goto out;
err:
printk(KERN_DEBUG PREFIX "err code %x\n", data);
switch (data) {
case HP_SDC_HIL_RC_DONE:
printk(KERN_WARNING PREFIX "Bastard SDC reconfigured loop!\n");
break;
case HP_SDC_HIL_ERR:
mlc->ipacket[idx] |= HIL_ERR_INT | HIL_ERR_PERR |
HIL_ERR_FERR | HIL_ERR_FOF;
break;
case HP_SDC_HIL_TO:
mlc->ipacket[idx] |= HIL_ERR_INT | HIL_ERR_LERR;
break;
case HP_SDC_HIL_RC:
printk(KERN_WARNING PREFIX "Bastard SDC decided to reconfigure loop!\n");
break;
default:
printk(KERN_WARNING PREFIX "Unkown HIL Error status (%x)!\n", data);
break;
}
/* No more data will be coming due to an error. */
done:
tasklet_schedule(mlc->tasklet);
up(&(mlc->isem));
out:
write_unlock(&(mlc->lock));
}
/******************** Tasklet or userspace context functions ****************/
static int hp_sdc_mlc_in (hil_mlc *mlc, suseconds_t timeout) {
unsigned long flags;
struct hp_sdc_mlc_priv_s *priv;
int rc = 2;
priv = mlc->priv;
write_lock_irqsave(&(mlc->lock), flags);
/* Try to down the semaphore */
if (down_trylock(&(mlc->isem))) {
struct timeval tv;
if (priv->emtestmode) {
mlc->ipacket[0] =
HIL_ERR_INT | (mlc->opacket &
(HIL_PKT_CMD |
HIL_PKT_ADDR_MASK |
HIL_PKT_DATA_MASK));
mlc->icount = 14;
/* printk(KERN_DEBUG PREFIX ">[%x]\n", mlc->ipacket[0]); */
goto wasup;
}
do_gettimeofday(&tv);
tv.tv_usec += 1000000 * (tv.tv_sec - mlc->instart.tv_sec);
if (tv.tv_usec - mlc->instart.tv_usec > mlc->intimeout) {
/* printk("!%i %i",
tv.tv_usec - mlc->instart.tv_usec,
mlc->intimeout);
*/
rc = 1;
up(&(mlc->isem));
}
goto done;
}
wasup:
up(&(mlc->isem));
rc = 0;
goto done;
done:
write_unlock_irqrestore(&(mlc->lock), flags);
return rc;
}
static int hp_sdc_mlc_cts (hil_mlc *mlc) {
struct hp_sdc_mlc_priv_s *priv;
unsigned long flags;
priv = mlc->priv;
write_lock_irqsave(&(mlc->lock), flags);
/* Try to down the semaphores -- they should be up. */
if (down_trylock(&(mlc->isem))) {
BUG();
goto busy;
}
if (down_trylock(&(mlc->osem))) {
BUG();
up(&(mlc->isem));
goto busy;
}
up(&(mlc->isem));
up(&(mlc->osem));
if (down_trylock(&(mlc->csem))) {
if (priv->trans.act.semaphore != &(mlc->csem)) goto poll;
goto busy;
}
if (!(priv->tseq[4] & HP_SDC_USE_LOOP)) goto done;
poll:
priv->trans.act.semaphore = &(mlc->csem);
priv->trans.actidx = 0;
priv->trans.idx = 1;
priv->trans.endidx = 5;
priv->tseq[0] =
HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN | HP_SDC_ACT_SEMAPHORE;
priv->tseq[1] = HP_SDC_CMD_READ_USE;
priv->tseq[2] = 1;
priv->tseq[3] = 0;
priv->tseq[4] = 0;
hp_sdc_enqueue_transaction(&(priv->trans));
busy:
write_unlock_irqrestore(&(mlc->lock), flags);
return 1;
done:
priv->trans.act.semaphore = &(mlc->osem);
up(&(mlc->csem));
write_unlock_irqrestore(&(mlc->lock), flags);
return 0;
}
static void hp_sdc_mlc_out (hil_mlc *mlc) {
struct hp_sdc_mlc_priv_s *priv;
unsigned long flags;
priv = mlc->priv;
write_lock_irqsave(&(mlc->lock), flags);
/* Try to down the semaphore -- it should be up. */
if (down_trylock(&(mlc->osem))) {
BUG();
goto done;
}
if (mlc->opacket & HIL_DO_ALTER_CTRL) goto do_control;
do_data:
if (priv->emtestmode) {
up(&(mlc->osem));
goto done;
}
/* Shouldn't be sending commands when loop may be busy */
if (down_trylock(&(mlc->csem))) {
BUG();
goto done;
}
up(&(mlc->csem));
priv->trans.actidx = 0;
priv->trans.idx = 1;
priv->trans.act.semaphore = &(mlc->osem);
priv->trans.endidx = 6;
priv->tseq[0] =
HP_SDC_ACT_DATAREG | HP_SDC_ACT_POSTCMD | HP_SDC_ACT_SEMAPHORE;
priv->tseq[1] = 0x7;
priv->tseq[2] =
(mlc->opacket &
(HIL_PKT_ADDR_MASK | HIL_PKT_CMD))
>> HIL_PKT_ADDR_SHIFT;
priv->tseq[3] =
(mlc->opacket & HIL_PKT_DATA_MASK)
>> HIL_PKT_DATA_SHIFT;
priv->tseq[4] = 0; /* No timeout */
if (priv->tseq[3] == HIL_CMD_DHR) priv->tseq[4] = 1;
priv->tseq[5] = HP_SDC_CMD_DO_HIL;
goto enqueue;
do_control:
priv->emtestmode = mlc->opacket & HIL_CTRL_TEST;
/* we cannot emulate this, it should not be used. */
BUG_ON((mlc->opacket & (HIL_CTRL_APE | HIL_CTRL_IPF)) == HIL_CTRL_APE);
if ((mlc->opacket & HIL_CTRL_ONLY) == HIL_CTRL_ONLY) goto control_only;
if (mlc->opacket & HIL_CTRL_APE) {
BUG(); /* Should not send command/data after engaging APE */
goto done;
}
/* Disengaging APE this way would not be valid either since
* the loop must be allowed to idle.
*
* So, it works out that we really never actually send control
* and data when using SDC, we just send the data.
*/
goto do_data;
control_only:
priv->trans.actidx = 0;
priv->trans.idx = 1;
priv->trans.act.semaphore = &(mlc->osem);
priv->trans.endidx = 4;
priv->tseq[0] =
HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT | HP_SDC_ACT_SEMAPHORE;
priv->tseq[1] = HP_SDC_CMD_SET_LPC;
priv->tseq[2] = 1;
// priv->tseq[3] = (mlc->ddc + 1) | HP_SDC_LPS_ACSUCC;
priv->tseq[3] = 0;
if (mlc->opacket & HIL_CTRL_APE) {
priv->tseq[3] |= HP_SDC_LPC_APE_IPF;
down_trylock(&(mlc->csem));
}
enqueue:
hp_sdc_enqueue_transaction(&(priv->trans));
done:
write_unlock_irqrestore(&(mlc->lock), flags);
}
static int __init hp_sdc_mlc_init(void)
{
hil_mlc *mlc = &hp_sdc_mlc;
printk(KERN_INFO PREFIX "Registering the System Domain Controller's HIL MLC.\n");
hp_sdc_mlc_priv.emtestmode = 0;
hp_sdc_mlc_priv.trans.seq = hp_sdc_mlc_priv.tseq;
hp_sdc_mlc_priv.trans.act.semaphore = &(mlc->osem);
hp_sdc_mlc_priv.got5x = 0;
mlc->cts = &hp_sdc_mlc_cts;
mlc->in = &hp_sdc_mlc_in;
mlc->out = &hp_sdc_mlc_out;
if (hil_mlc_register(mlc)) {
printk(KERN_WARNING PREFIX "Failed to register MLC structure with hil_mlc\n");
goto err0;
}
mlc->priv = &hp_sdc_mlc_priv;
if (hp_sdc_request_hil_irq(&hp_sdc_mlc_isr)) {
printk(KERN_WARNING PREFIX "Request for raw HIL ISR hook denied\n");
goto err1;
}
return 0;
err1:
if (hil_mlc_unregister(mlc)) {
printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n"
"This is bad. Could cause an oops.\n");
}
err0:
return -EBUSY;
}
static void __exit hp_sdc_mlc_exit(void)
{
hil_mlc *mlc = &hp_sdc_mlc;
if (hp_sdc_release_hil_irq(&hp_sdc_mlc_isr)) {
printk(KERN_ERR PREFIX "Failed to release the raw HIL ISR hook.\n"
"This is bad. Could cause an oops.\n");
}
if (hil_mlc_unregister(mlc)) {
printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n"
"This is bad. Could cause an oops.\n");
}
}
module_init(hp_sdc_mlc_init);
module_exit(hp_sdc_mlc_exit);
