asgardius/android_kernel_motorola_sm6225
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
android_kernel_motorola_sm6225/drivers/scsi/NCR5380.h
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
14 KiB
C
Raw Blame History

/*
* NCR 5380 defines
*
* Copyright 1993, Drew Eckhardt
* Visionary Computing
* (Unix consulting and custom programming)
* drew@colorado.edu
* +1 (303) 666-5836
*
* DISTRIBUTION RELEASE 7
*
* For more information, please consult
*
* NCR 5380 Family
* SCSI Protocol Controller
* Databook
* NCR Microelectronics
* 1635 Aeroplaza Drive
* Colorado Springs, CO 80916
* 1+ (719) 578-3400
* 1+ (800) 334-5454
*/
/*
* $Log: NCR5380.h,v $
*/
#ifndef NCR5380_H
#define NCR5380_H
#include <linux/interrupt.h>
#define NCR5380_PUBLIC_RELEASE 7
#define NCR53C400_PUBLIC_RELEASE 2
#define NDEBUG_ARBITRATION 0x1
#define NDEBUG_AUTOSENSE 0x2
#define NDEBUG_DMA 0x4
#define NDEBUG_HANDSHAKE 0x8
#define NDEBUG_INFORMATION 0x10
#define NDEBUG_INIT 0x20
#define NDEBUG_INTR 0x40
#define NDEBUG_LINKED 0x80
#define NDEBUG_MAIN 0x100
#define NDEBUG_NO_DATAOUT 0x200
#define NDEBUG_NO_WRITE 0x400
#define NDEBUG_PIO 0x800
#define NDEBUG_PSEUDO_DMA 0x1000
#define NDEBUG_QUEUES 0x2000
#define NDEBUG_RESELECTION 0x4000
#define NDEBUG_SELECTION 0x8000
#define NDEBUG_USLEEP 0x10000
#define NDEBUG_LAST_BYTE_SENT 0x20000
#define NDEBUG_RESTART_SELECT 0x40000
#define NDEBUG_EXTENDED 0x80000
#define NDEBUG_C400_PREAD 0x100000
#define NDEBUG_C400_PWRITE 0x200000
#define NDEBUG_LISTS 0x400000
#define NDEBUG_ANY 0xFFFFFFFFUL
/*
* The contents of the OUTPUT DATA register are asserted on the bus when
* either arbitration is occurring or the phase-indicating signals (
* IO, CD, MSG) in the TARGET COMMAND register and the ASSERT DATA
* bit in the INITIATOR COMMAND register is set.
*/
#define OUTPUT_DATA_REG 0 /* wo DATA lines on SCSI bus */
#define CURRENT_SCSI_DATA_REG 0 /* ro same */
#define INITIATOR_COMMAND_REG 1 /* rw */
#define ICR_ASSERT_RST 0x80 /* rw Set to assert RST */
#define ICR_ARBITRATION_PROGRESS 0x40 /* ro Indicates arbitration complete */
#define ICR_TRI_STATE 0x40 /* wo Set to tri-state drivers */
#define ICR_ARBITRATION_LOST 0x20 /* ro Indicates arbitration lost */
#define ICR_DIFF_ENABLE 0x20 /* wo Set to enable diff. drivers */
#define ICR_ASSERT_ACK 0x10 /* rw ini Set to assert ACK */
#define ICR_ASSERT_BSY 0x08 /* rw Set to assert BSY */
#define ICR_ASSERT_SEL 0x04 /* rw Set to assert SEL */
#define ICR_ASSERT_ATN 0x02 /* rw Set to assert ATN */
#define ICR_ASSERT_DATA 0x01 /* rw SCSI_DATA_REG is asserted */
#ifdef DIFFERENTIAL
#define ICR_BASE ICR_DIFF_ENABLE
#else
#define ICR_BASE 0
#endif
#define MODE_REG 2
/*
* Note : BLOCK_DMA code will keep DRQ asserted for the duration of the
* transfer, causing the chip to hog the bus. You probably don't want
* this.
*/
#define MR_BLOCK_DMA_MODE 0x80 /* rw block mode DMA */
#define MR_TARGET 0x40 /* rw target mode */
#define MR_ENABLE_PAR_CHECK 0x20 /* rw enable parity checking */
#define MR_ENABLE_PAR_INTR 0x10 /* rw enable bad parity interrupt */
#define MR_ENABLE_EOP_INTR 0x08 /* rw enable eop interrupt */
#define MR_MONITOR_BSY 0x04 /* rw enable int on unexpected bsy fail */
#define MR_DMA_MODE 0x02 /* rw DMA / pseudo DMA mode */
#define MR_ARBITRATE 0x01 /* rw start arbitration */
#ifdef PARITY
#define MR_BASE MR_ENABLE_PAR_CHECK
#else
#define MR_BASE 0
#endif
#define TARGET_COMMAND_REG 3
#define TCR_LAST_BYTE_SENT 0x80 /* ro DMA done */
#define TCR_ASSERT_REQ 0x08 /* tgt rw assert REQ */
#define TCR_ASSERT_MSG 0x04 /* tgt rw assert MSG */
#define TCR_ASSERT_CD 0x02 /* tgt rw assert CD */
#define TCR_ASSERT_IO 0x01 /* tgt rw assert IO */
#define STATUS_REG 4 /* ro */
/*
* Note : a set bit indicates an active signal, driven by us or another
* device.
*/
#define SR_RST 0x80
#define SR_BSY 0x40
#define SR_REQ 0x20
#define SR_MSG 0x10
#define SR_CD 0x08
#define SR_IO 0x04
#define SR_SEL 0x02
#define SR_DBP 0x01
/*
* Setting a bit in this register will cause an interrupt to be generated when
* BSY is false and SEL true and this bit is asserted on the bus.
*/
#define SELECT_ENABLE_REG 4 /* wo */
#define BUS_AND_STATUS_REG 5 /* ro */
#define BASR_END_DMA_TRANSFER 0x80 /* ro set on end of transfer */
#define BASR_DRQ 0x40 /* ro mirror of DRQ pin */
#define BASR_PARITY_ERROR 0x20 /* ro parity error detected */
#define BASR_IRQ 0x10 /* ro mirror of IRQ pin */
#define BASR_PHASE_MATCH 0x08 /* ro Set when MSG CD IO match TCR */
#define BASR_BUSY_ERROR 0x04 /* ro Unexpected change to inactive state */
#define BASR_ATN 0x02 /* ro BUS status */
#define BASR_ACK 0x01 /* ro BUS status */
/* Write any value to this register to start a DMA send */
#define START_DMA_SEND_REG 5 /* wo */
/*
* Used in DMA transfer mode, data is latched from the SCSI bus on
* the falling edge of REQ (ini) or ACK (tgt)
*/
#define INPUT_DATA_REG 6 /* ro */
/* Write any value to this register to start a DMA receive */
#define START_DMA_TARGET_RECEIVE_REG 6 /* wo */
/* Read this register to clear interrupt conditions */
#define RESET_PARITY_INTERRUPT_REG 7 /* ro */
/* Write any value to this register to start an ini mode DMA receive */
#define START_DMA_INITIATOR_RECEIVE_REG 7 /* wo */
#define C400_CONTROL_STATUS_REG NCR53C400_register_offset-8 /* rw */
#define CSR_RESET 0x80 /* wo Resets 53c400 */
#define CSR_53C80_REG 0x80 /* ro 5380 registers busy */
#define CSR_TRANS_DIR 0x40 /* rw Data transfer direction */
#define CSR_SCSI_BUFF_INTR 0x20 /* rw Enable int on transfer ready */
#define CSR_53C80_INTR 0x10 /* rw Enable 53c80 interrupts */
#define CSR_SHARED_INTR 0x08 /* rw Interrupt sharing */
#define CSR_HOST_BUF_NOT_RDY 0x04 /* ro Is Host buffer ready */
#define CSR_SCSI_BUF_RDY 0x02 /* ro SCSI buffer read */
#define CSR_GATED_53C80_IRQ 0x01 /* ro Last block xferred */
#if 0
#define CSR_BASE CSR_SCSI_BUFF_INTR | CSR_53C80_INTR
#else
#define CSR_BASE CSR_53C80_INTR
#endif
/* Number of 128-byte blocks to be transferred */
#define C400_BLOCK_COUNTER_REG NCR53C400_register_offset-7 /* rw */
/* Resume transfer after disconnect */
#define C400_RESUME_TRANSFER_REG NCR53C400_register_offset-6 /* wo */
/* Access to host buffer stack */
#define C400_HOST_BUFFER NCR53C400_register_offset-4 /* rw */
/* Note : PHASE_* macros are based on the values of the STATUS register */
#define PHASE_MASK (SR_MSG | SR_CD | SR_IO)
#define PHASE_DATAOUT 0
#define PHASE_DATAIN SR_IO
#define PHASE_CMDOUT SR_CD
#define PHASE_STATIN (SR_CD | SR_IO)
#define PHASE_MSGOUT (SR_MSG | SR_CD)
#define PHASE_MSGIN (SR_MSG | SR_CD | SR_IO)
#define PHASE_UNKNOWN 0xff
/*
* Convert status register phase to something we can use to set phase in
* the target register so we can get phase mismatch interrupts on DMA
* transfers.
*/
#define PHASE_SR_TO_TCR(phase) ((phase) >> 2)
/*
* The internal should_disconnect() function returns these based on the
* expected length of a disconnect if a device supports disconnect/
* reconnect.
*/
#define DISCONNECT_NONE 0
#define DISCONNECT_TIME_TO_DATA 1
#define DISCONNECT_LONG 2
/*
* These are "special" values for the tag parameter passed to NCR5380_select.
*/
#define TAG_NEXT -1 /* Use next free tag */
#define TAG_NONE -2 /*
* Establish I_T_L nexus instead of I_T_L_Q
* even on SCSI-II devices.
*/
/*
* These are "special" values for the irq and dma_channel fields of the
* Scsi_Host structure
*/
#define SCSI_IRQ_NONE 255
#define DMA_NONE 255
#define IRQ_AUTO 254
#define DMA_AUTO 254
#define PORT_AUTO 0xffff /* autoprobe io port for 53c400a */
#define FLAG_HAS_LAST_BYTE_SENT 1 /* NCR53c81 or better */
#define FLAG_CHECK_LAST_BYTE_SENT 2 /* Only test once */
#define FLAG_NCR53C400 4 /* NCR53c400 */
#define FLAG_NO_PSEUDO_DMA 8 /* Inhibit DMA */
#define FLAG_DTC3181E 16 /* DTC3181E */
#ifndef ASM
struct NCR5380_hostdata {
NCR5380_implementation_fields; /* implementation specific */
struct Scsi_Host *host; /* Host backpointer */
unsigned char id_mask, id_higher_mask; /* 1 << id, all bits greater */
unsigned char targets_present; /* targets we have connected
to, so we can call a select
failure a retryable condition */
volatile unsigned char busy[8]; /* index = target, bit = lun */
#if defined(REAL_DMA) || defined(REAL_DMA_POLL)
volatile int dma_len; /* requested length of DMA */
#endif
volatile unsigned char last_message; /* last message OUT */
volatile Scsi_Cmnd *connected; /* currently connected command */
volatile Scsi_Cmnd *issue_queue; /* waiting to be issued */
volatile Scsi_Cmnd *disconnected_queue; /* waiting for reconnect */
volatile int restart_select; /* we have disconnected,
used to restart
NCR5380_select() */
volatile unsigned aborted:1; /* flag, says aborted */
int flags;
unsigned long time_expires; /* in jiffies, set prior to sleeping */
int select_time; /* timer in select for target response */
volatile Scsi_Cmnd *selecting;
struct work_struct coroutine; /* our co-routine */
#ifdef NCR5380_STATS
unsigned timebase; /* Base for time calcs */
long time_read[8]; /* time to do reads */
long time_write[8]; /* time to do writes */
unsigned long bytes_read[8]; /* bytes read */
unsigned long bytes_write[8]; /* bytes written */
unsigned pendingr;
unsigned pendingw;
#endif
};
#ifdef __KERNEL__
#define dprintk(a,b) do {} while(0)
#define NCR5380_dprint(a,b) do {} while(0)
#define NCR5380_dprint_phase(a,b) do {} while(0)
#if defined(AUTOPROBE_IRQ)
static int NCR5380_probe_irq(struct Scsi_Host *instance, int possible);
#endif
static int NCR5380_init(struct Scsi_Host *instance, int flags);
static void NCR5380_exit(struct Scsi_Host *instance);
static void NCR5380_information_transfer(struct Scsi_Host *instance);
#ifndef DONT_USE_INTR
static irqreturn_t NCR5380_intr(int irq, void *dev_id);
#endif
static void NCR5380_main(void *ptr);
static void NCR5380_print_options(struct Scsi_Host *instance);
#ifdef NDEBUG
static void NCR5380_print_phase(struct Scsi_Host *instance);
static void NCR5380_print(struct Scsi_Host *instance);
#endif
static int NCR5380_abort(Scsi_Cmnd * cmd);
static int NCR5380_bus_reset(Scsi_Cmnd * cmd);
static int NCR5380_queue_command(Scsi_Cmnd * cmd, void (*done) (Scsi_Cmnd *));
static int NCR5380_proc_info(struct Scsi_Host *instance, char *buffer, char **start,
off_t offset, int length, int inout);
static void NCR5380_reselect(struct Scsi_Host *instance);
static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd * cmd, int tag);
#if defined(PSEUDO_DMA) || defined(REAL_DMA) || defined(REAL_DMA_POLL)
static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data);
#endif
static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data);
#if (defined(REAL_DMA) || defined(REAL_DMA_POLL))
#if defined(i386) || defined(__alpha__)
/**
* NCR5380_pc_dma_setup - setup ISA DMA
* @instance: adapter to set up
* @ptr: block to transfer (virtual address)
* @count: number of bytes to transfer
* @mode: DMA controller mode to use
*
* Program the DMA controller ready to perform an ISA DMA transfer
* on this chip.
*
* Locks: takes and releases the ISA DMA lock.
*/
static __inline__ int NCR5380_pc_dma_setup(struct Scsi_Host *instance, unsigned char *ptr, unsigned int count, unsigned char mode)
{
unsigned limit;
unsigned long bus_addr = virt_to_bus(ptr);
unsigned long flags;
if (instance->dma_channel <= 3) {
if (count > 65536)
count = 65536;
limit = 65536 - (bus_addr & 0xFFFF);
} else {
if (count > 65536 * 2)
count = 65536 * 2;
limit = 65536 * 2 - (bus_addr & 0x1FFFF);
}
if (count > limit)
count = limit;
if ((count & 1) || (bus_addr & 1))
panic("scsi%d : attempted unaligned DMA transfer\n", instance->host_no);
flags=claim_dma_lock();
disable_dma(instance->dma_channel);
clear_dma_ff(instance->dma_channel);
set_dma_addr(instance->dma_channel, bus_addr);
set_dma_count(instance->dma_channel, count);
set_dma_mode(instance->dma_channel, mode);
enable_dma(instance->dma_channel);
release_dma_lock(flags);
return count;
}
/**
* NCR5380_pc_dma_write_setup - setup ISA DMA write
* @instance: adapter to set up
* @ptr: block to transfer (virtual address)
* @count: number of bytes to transfer
*
* Program the DMA controller ready to perform an ISA DMA write to the
* SCSI controller.
*
* Locks: called routines take and release the ISA DMA lock.
*/
static __inline__ int NCR5380_pc_dma_write_setup(struct Scsi_Host *instance, unsigned char *src, unsigned int count)
{
return NCR5380_pc_dma_setup(instance, src, count, DMA_MODE_WRITE);
}
/**
* NCR5380_pc_dma_read_setup - setup ISA DMA read
* @instance: adapter to set up
* @ptr: block to transfer (virtual address)
* @count: number of bytes to transfer
*
* Program the DMA controller ready to perform an ISA DMA read from the
* SCSI controller.
*
* Locks: called routines take and release the ISA DMA lock.
*/
static __inline__ int NCR5380_pc_dma_read_setup(struct Scsi_Host *instance, unsigned char *src, unsigned int count)
{
return NCR5380_pc_dma_setup(instance, src, count, DMA_MODE_READ);
}
/**
* NCR5380_pc_dma_residual - return bytes left
* @instance: adapter
*
* Reports the number of bytes left over after the DMA was terminated.
*
* Locks: takes and releases the ISA DMA lock.
*/
static __inline__ int NCR5380_pc_dma_residual(struct Scsi_Host *instance)
{
unsigned long flags;
int tmp;
flags = claim_dma_lock();
clear_dma_ff(instance->dma_channel);
tmp = get_dma_residue(instance->dma_channel);
release_dma_lock(flags);
return tmp;
}
#endif /* defined(i386) || defined(__alpha__) */
#endif /* defined(REAL_DMA) */
#endif /* __KERNEL__ */
#endif /* ndef ASM */
#endif /* NCR5380_H */
Reference in a new issue View git blame Copy permalink