android_kernel_samsung_msm8976/drivers/media/dvb/b2c2/flexcop-pci.c
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00

430 lines
12 KiB
C

/*
* This file is part of linux driver the digital TV devices equipped with B2C2 FlexcopII(b)/III
*
* flexcop-pci.c - covers the PCI part including DMA transfers.
*
* see flexcop.c for copyright information.
*/
#define FC_LOG_PREFIX "flexcop-pci"
#include "flexcop-common.h"
static int enable_pid_filtering = 1;
module_param(enable_pid_filtering, int, 0444);
MODULE_PARM_DESC(enable_pid_filtering, "enable hardware pid filtering: supported values: 0 (fullts), 1");
static int irq_chk_intv;
module_param(irq_chk_intv, int, 0644);
MODULE_PARM_DESC(irq_chk_intv, "set the interval for IRQ watchdog (currently just debugging).");
#ifdef CONFIG_DVB_B2C2_FLEXCOP_DEBUG
#define dprintk(level,args...) \
do { if ((debug & level)) printk(args); } while (0)
#define DEBSTATUS ""
#else
#define dprintk(level,args...)
#define DEBSTATUS " (debugging is not enabled)"
#endif
#define deb_info(args...) dprintk(0x01,args)
#define deb_reg(args...) dprintk(0x02,args)
#define deb_ts(args...) dprintk(0x04,args)
#define deb_irq(args...) dprintk(0x08,args)
#define deb_chk(args...) dprintk(0x10,args)
static int debug = 0;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "set debug level (1=info,2=regs,4=TS,8=irqdma (|-able))." DEBSTATUS);
#define DRIVER_VERSION "0.1"
#define DRIVER_NAME "Technisat/B2C2 FlexCop II/IIb/III Digital TV PCI Driver"
#define DRIVER_AUTHOR "Patrick Boettcher <patrick.boettcher@desy.de>"
struct flexcop_pci {
struct pci_dev *pdev;
#define FC_PCI_INIT 0x01
#define FC_PCI_DMA_INIT 0x02
int init_state;
void __iomem *io_mem;
u32 irq;
/* buffersize (at least for DMA1, need to be % 188 == 0,
* this logic is required */
#define FC_DEFAULT_DMA1_BUFSIZE (1280 * 188)
#define FC_DEFAULT_DMA2_BUFSIZE (10 * 188)
struct flexcop_dma dma[2];
int active_dma1_addr; /* 0 = addr0 of dma1; 1 = addr1 of dma1 */
u32 last_dma1_cur_pos; /* position of the pointer last time the timer/packet irq occured */
int count;
spinlock_t irq_lock;
unsigned long last_irq;
struct work_struct irq_check_work;
struct flexcop_device *fc_dev;
};
static int lastwreg,lastwval,lastrreg,lastrval;
static flexcop_ibi_value flexcop_pci_read_ibi_reg (struct flexcop_device *fc, flexcop_ibi_register r)
{
struct flexcop_pci *fc_pci = fc->bus_specific;
flexcop_ibi_value v;
v.raw = readl(fc_pci->io_mem + r);
if (lastrreg != r || lastrval != v.raw) {
lastrreg = r; lastrval = v.raw;
deb_reg("new rd: %3x: %08x\n",r,v.raw);
}
return v;
}
static int flexcop_pci_write_ibi_reg(struct flexcop_device *fc, flexcop_ibi_register r, flexcop_ibi_value v)
{
struct flexcop_pci *fc_pci = fc->bus_specific;
if (lastwreg != r || lastwval != v.raw) {
lastwreg = r; lastwval = v.raw;
deb_reg("new wr: %3x: %08x\n",r,v.raw);
}
writel(v.raw, fc_pci->io_mem + r);
return 0;
}
static void flexcop_pci_irq_check_work(void *data)
{
struct flexcop_pci *fc_pci = data;
struct flexcop_device *fc = fc_pci->fc_dev;
flexcop_ibi_value v = fc->read_ibi_reg(fc,sram_dest_reg_714);
flexcop_dump_reg(fc_pci->fc_dev,dma1_000,4);
if (v.sram_dest_reg_714.net_ovflow_error)
deb_chk("sram net_ovflow_error\n");
if (v.sram_dest_reg_714.media_ovflow_error)
deb_chk("sram media_ovflow_error\n");
if (v.sram_dest_reg_714.cai_ovflow_error)
deb_chk("sram cai_ovflow_error\n");
if (v.sram_dest_reg_714.cai_ovflow_error)
deb_chk("sram cai_ovflow_error\n");
schedule_delayed_work(&fc_pci->irq_check_work,
msecs_to_jiffies(irq_chk_intv < 100 ? 100 : irq_chk_intv));
}
/* When PID filtering is turned on, we use the timer IRQ, because small amounts
* of data need to be passed to the user space instantly as well. When PID
* filtering is turned off, we use the page-change-IRQ */
static irqreturn_t flexcop_pci_isr(int irq, void *dev_id)
{
struct flexcop_pci *fc_pci = dev_id;
struct flexcop_device *fc = fc_pci->fc_dev;
flexcop_ibi_value v;
irqreturn_t ret = IRQ_HANDLED;
spin_lock_irq(&fc_pci->irq_lock);
v = fc->read_ibi_reg(fc,irq_20c);
/* errors */
if (v.irq_20c.Data_receiver_error)
deb_chk("data receiver error\n");
if (v.irq_20c.Continuity_error_flag)
deb_chk("Contunuity error flag is set\n");
if (v.irq_20c.LLC_SNAP_FLAG_set)
deb_chk("LLC_SNAP_FLAG_set is set\n");
if (v.irq_20c.Transport_Error)
deb_chk("Transport error\n");
if ((fc_pci->count % 1000) == 0)
deb_chk("%d valid irq took place so far\n",fc_pci->count);
if (v.irq_20c.DMA1_IRQ_Status == 1) {
if (fc_pci->active_dma1_addr == 0)
flexcop_pass_dmx_packets(fc_pci->fc_dev,fc_pci->dma[0].cpu_addr0,fc_pci->dma[0].size / 188);
else
flexcop_pass_dmx_packets(fc_pci->fc_dev,fc_pci->dma[0].cpu_addr1,fc_pci->dma[0].size / 188);
deb_irq("page change to page: %d\n",!fc_pci->active_dma1_addr);
fc_pci->active_dma1_addr = !fc_pci->active_dma1_addr;
} else if (v.irq_20c.DMA1_Timer_Status == 1) {
/* for the timer IRQ we only can use buffer dmx feeding, because we don't have
* complete TS packets when reading from the DMA memory */
dma_addr_t cur_addr =
fc->read_ibi_reg(fc,dma1_008).dma_0x8.dma_cur_addr << 2;
u32 cur_pos = cur_addr - fc_pci->dma[0].dma_addr0;
deb_irq("%u irq: %08x cur_addr: %llx: cur_pos: %08x, last_cur_pos: %08x ",
jiffies_to_usecs(jiffies - fc_pci->last_irq),
v.raw, (unsigned long long)cur_addr, cur_pos,
fc_pci->last_dma1_cur_pos);
fc_pci->last_irq = jiffies;
/* buffer end was reached, restarted from the beginning
* pass the data from last_cur_pos to the buffer end to the demux
*/
if (cur_pos < fc_pci->last_dma1_cur_pos) {
deb_irq(" end was reached: passing %d bytes ",(fc_pci->dma[0].size*2 - 1) - fc_pci->last_dma1_cur_pos);
flexcop_pass_dmx_data(fc_pci->fc_dev,
fc_pci->dma[0].cpu_addr0 + fc_pci->last_dma1_cur_pos,
(fc_pci->dma[0].size*2) - fc_pci->last_dma1_cur_pos);
fc_pci->last_dma1_cur_pos = 0;
}
if (cur_pos > fc_pci->last_dma1_cur_pos) {
deb_irq(" passing %d bytes ",cur_pos - fc_pci->last_dma1_cur_pos);
flexcop_pass_dmx_data(fc_pci->fc_dev,
fc_pci->dma[0].cpu_addr0 + fc_pci->last_dma1_cur_pos,
cur_pos - fc_pci->last_dma1_cur_pos);
}
deb_irq("\n");
fc_pci->last_dma1_cur_pos = cur_pos;
fc_pci->count++;
} else {
deb_irq("isr for flexcop called, apparently without reason (%08x)\n",v.raw);
ret = IRQ_NONE;
}
spin_unlock_irq(&fc_pci->irq_lock);
return ret;
}
static int flexcop_pci_stream_control(struct flexcop_device *fc, int onoff)
{
struct flexcop_pci *fc_pci = fc->bus_specific;
if (onoff) {
flexcop_dma_config(fc,&fc_pci->dma[0],FC_DMA_1);
flexcop_dma_config(fc,&fc_pci->dma[1],FC_DMA_2);
flexcop_dma_config_timer(fc,FC_DMA_1,0);
flexcop_dma_xfer_control(fc,FC_DMA_1,FC_DMA_SUBADDR_0 | FC_DMA_SUBADDR_1,1);
deb_irq("DMA xfer enabled\n");
fc_pci->last_dma1_cur_pos = 0;
flexcop_dma_control_timer_irq(fc,FC_DMA_1,1);
deb_irq("IRQ enabled\n");
// fc_pci->active_dma1_addr = 0;
// flexcop_dma_control_size_irq(fc,FC_DMA_1,1);
if (irq_chk_intv > 0)
schedule_delayed_work(&fc_pci->irq_check_work,
msecs_to_jiffies(irq_chk_intv < 100 ? 100 : irq_chk_intv));
} else {
if (irq_chk_intv > 0)
cancel_delayed_work(&fc_pci->irq_check_work);
flexcop_dma_control_timer_irq(fc,FC_DMA_1,0);
deb_irq("IRQ disabled\n");
// flexcop_dma_control_size_irq(fc,FC_DMA_1,0);
flexcop_dma_xfer_control(fc,FC_DMA_1,FC_DMA_SUBADDR_0 | FC_DMA_SUBADDR_1,0);
deb_irq("DMA xfer disabled\n");
}
return 0;
}
static int flexcop_pci_dma_init(struct flexcop_pci *fc_pci)
{
int ret;
if ((ret = flexcop_dma_allocate(fc_pci->pdev,&fc_pci->dma[0],FC_DEFAULT_DMA1_BUFSIZE)) != 0)
return ret;
if ((ret = flexcop_dma_allocate(fc_pci->pdev,&fc_pci->dma[1],FC_DEFAULT_DMA2_BUFSIZE)) != 0) {
flexcop_dma_free(&fc_pci->dma[0]);
return ret;
}
flexcop_sram_set_dest(fc_pci->fc_dev,FC_SRAM_DEST_MEDIA | FC_SRAM_DEST_NET, FC_SRAM_DEST_TARGET_DMA1);
flexcop_sram_set_dest(fc_pci->fc_dev,FC_SRAM_DEST_CAO | FC_SRAM_DEST_CAI, FC_SRAM_DEST_TARGET_DMA2);
fc_pci->init_state |= FC_PCI_DMA_INIT;
return ret;
}
static void flexcop_pci_dma_exit(struct flexcop_pci *fc_pci)
{
if (fc_pci->init_state & FC_PCI_DMA_INIT) {
flexcop_dma_free(&fc_pci->dma[0]);
flexcop_dma_free(&fc_pci->dma[1]);
}
fc_pci->init_state &= ~FC_PCI_DMA_INIT;
}
static int flexcop_pci_init(struct flexcop_pci *fc_pci)
{
int ret;
u8 card_rev;
pci_read_config_byte(fc_pci->pdev, PCI_CLASS_REVISION, &card_rev);
info("card revision %x", card_rev);
if ((ret = pci_enable_device(fc_pci->pdev)) != 0)
return ret;
pci_set_master(fc_pci->pdev);
/* enable interrupts */
// pci_write_config_dword(pdev, 0x6c, 0x8000);
if ((ret = pci_request_regions(fc_pci->pdev, DRIVER_NAME)) != 0)
goto err_pci_disable_device;
fc_pci->io_mem = pci_iomap(fc_pci->pdev, 0, 0x800);
if (!fc_pci->io_mem) {
err("cannot map io memory\n");
ret = -EIO;
goto err_pci_release_regions;
}
pci_set_drvdata(fc_pci->pdev, fc_pci);
if ((ret = request_irq(fc_pci->pdev->irq, flexcop_pci_isr,
IRQF_SHARED, DRIVER_NAME, fc_pci)) != 0)
goto err_pci_iounmap;
spin_lock_init(&fc_pci->irq_lock);
fc_pci->init_state |= FC_PCI_INIT;
return ret;
err_pci_iounmap:
pci_iounmap(fc_pci->pdev, fc_pci->io_mem);
pci_set_drvdata(fc_pci->pdev, NULL);
err_pci_release_regions:
pci_release_regions(fc_pci->pdev);
err_pci_disable_device:
pci_disable_device(fc_pci->pdev);
return ret;
}
static void flexcop_pci_exit(struct flexcop_pci *fc_pci)
{
if (fc_pci->init_state & FC_PCI_INIT) {
free_irq(fc_pci->pdev->irq, fc_pci);
pci_iounmap(fc_pci->pdev, fc_pci->io_mem);
pci_set_drvdata(fc_pci->pdev, NULL);
pci_release_regions(fc_pci->pdev);
pci_disable_device(fc_pci->pdev);
}
fc_pci->init_state &= ~FC_PCI_INIT;
}
static int flexcop_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
struct flexcop_device *fc;
struct flexcop_pci *fc_pci;
int ret = -ENOMEM;
if ((fc = flexcop_device_kmalloc(sizeof(struct flexcop_pci))) == NULL) {
err("out of memory\n");
return -ENOMEM;
}
/* general flexcop init */
fc_pci = fc->bus_specific;
fc_pci->fc_dev = fc;
fc->read_ibi_reg = flexcop_pci_read_ibi_reg;
fc->write_ibi_reg = flexcop_pci_write_ibi_reg;
fc->i2c_request = flexcop_i2c_request;
fc->get_mac_addr = flexcop_eeprom_check_mac_addr;
fc->stream_control = flexcop_pci_stream_control;
if (enable_pid_filtering)
info("will use the HW PID filter.");
else
info("will pass the complete TS to the demuxer.");
fc->pid_filtering = enable_pid_filtering;
fc->bus_type = FC_PCI;
fc->dev = &pdev->dev;
fc->owner = THIS_MODULE;
/* bus specific part */
fc_pci->pdev = pdev;
if ((ret = flexcop_pci_init(fc_pci)) != 0)
goto err_kfree;
/* init flexcop */
if ((ret = flexcop_device_initialize(fc)) != 0)
goto err_pci_exit;
/* init dma */
if ((ret = flexcop_pci_dma_init(fc_pci)) != 0)
goto err_fc_exit;
INIT_WORK(&fc_pci->irq_check_work, flexcop_pci_irq_check_work, fc_pci);
return ret;
err_fc_exit:
flexcop_device_exit(fc);
err_pci_exit:
flexcop_pci_exit(fc_pci);
err_kfree:
flexcop_device_kfree(fc);
return ret;
}
/* in theory every _exit function should be called exactly two times,
* here and in the bail-out-part of the _init-function
*/
static void flexcop_pci_remove(struct pci_dev *pdev)
{
struct flexcop_pci *fc_pci = pci_get_drvdata(pdev);
flexcop_pci_dma_exit(fc_pci);
flexcop_device_exit(fc_pci->fc_dev);
flexcop_pci_exit(fc_pci);
flexcop_device_kfree(fc_pci->fc_dev);
}
static struct pci_device_id flexcop_pci_tbl[] = {
{ PCI_DEVICE(0x13d0, 0x2103) },
/* { PCI_DEVICE(0x13d0, 0x2200) }, ? */
{ },
};
MODULE_DEVICE_TABLE(pci, flexcop_pci_tbl);
static struct pci_driver flexcop_pci_driver = {
.name = "b2c2_flexcop_pci",
.id_table = flexcop_pci_tbl,
.probe = flexcop_pci_probe,
.remove = flexcop_pci_remove,
};
static int __init flexcop_pci_module_init(void)
{
return pci_register_driver(&flexcop_pci_driver);
}
static void __exit flexcop_pci_module_exit(void)
{
pci_unregister_driver(&flexcop_pci_driver);
}
module_init(flexcop_pci_module_init);
module_exit(flexcop_pci_module_exit);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_NAME);
MODULE_LICENSE("GPL");