tile: various console improvements

This change improves and cleans up the tile console.

- We enable HVC_IRQ support on tilegx, with the addition of a new
  Tilera hypervisor API for tilegx to allow a console IPI.  If IPI
  support is not available we fall back to the previous polling mode.

- We simplify the earlyprintk code to use CON_BOOT and eliminate some
  of the other supporting earlyprintk code.

- A new tile_console_write() primitive is used to send output to
  the console and is factored out of the hvc_tile driver.
  This lets us support a "sim_console" boot argument to allow using
  simulator hooks to send output to the "console" as a slightly
  faster alternative to emulating the hardware more directly.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Chris Metcalf 2013-08-06 14:11:21 -04:00
parent 7c29b78a0e
commit bda0f5bad8
7 changed files with 186 additions and 48 deletions

View File

@ -112,6 +112,7 @@ config SMP
config HVC_TILE
depends on TTY
select HVC_DRIVER
select HVC_IRQ if TILEGX
def_bool y
config TILEGX

View File

@ -24,9 +24,8 @@
*/
#define MAXMEM_PFN PFN_DOWN(MAXMEM)
int tile_console_write(const char *buf, int count);
void early_panic(const char *fmt, ...);
void warn_early_printk(void);
void __init disable_early_printk(void);
/* Init-time routine to do tile-specific per-cpu setup. */
void setup_cpu(int boot);

View File

@ -318,8 +318,11 @@
/** hv_set_pte_super_shift */
#define HV_DISPATCH_SET_PTE_SUPER_SHIFT 57
/** hv_console_set_ipi */
#define HV_DISPATCH_CONSOLE_SET_IPI 63
/** One more than the largest dispatch value */
#define _HV_DISPATCH_END 58
#define _HV_DISPATCH_END 64
#ifndef __ASSEMBLER__
@ -585,6 +588,30 @@ typedef struct
*/
int hv_get_ipi_pte(HV_Coord tile, int pl, HV_PTE* pte);
/** Configure the console interrupt.
*
* When the console client interrupt is enabled, the hypervisor will
* deliver the specified IPI to the client in the following situations:
*
* - The console has at least one character available for input.
*
* - The console can accept new characters for output, and the last call
* to hv_console_write() did not write all of the characters requested
* by the client.
*
* Note that in some system configurations, console interrupt will not
* be available; clients should be prepared for this routine to fail and
* to fall back to periodic console polling in that case.
*
* @param ipi Index of the IPI register which will receive the interrupt.
* @param event IPI event number for console interrupt. If less than 0,
* disable the console IPI interrupt.
* @param coord Tile to be targeted for console interrupt.
* @return 0 on success, otherwise, HV_EINVAL if illegal parameter,
* HV_ENOTSUP if console interrupt are not available.
*/
int hv_console_set_ipi(int ipi, int event, HV_Coord coord);
#else /* !CHIP_HAS_IPI() */
/** A set of interrupts. */

View File

@ -23,19 +23,24 @@
static void early_hv_write(struct console *con, const char *s, unsigned n)
{
hv_console_write((HV_VirtAddr) s, n);
tile_console_write(s, n);
/*
* Convert NL to NLCR (close enough to CRNL) during early boot.
* We assume newlines are at the ends of strings, which turns out
* to be good enough for early boot console output.
*/
if (n && s[n-1] == '\n')
tile_console_write("\r", 1);
}
static struct console early_hv_console = {
.name = "earlyhv",
.write = early_hv_write,
.flags = CON_PRINTBUFFER,
.flags = CON_PRINTBUFFER | CON_BOOT,
.index = -1,
};
/* Direct interface for emergencies */
static int early_console_complete;
void early_panic(const char *fmt, ...)
{
va_list ap;
@ -43,51 +48,21 @@ void early_panic(const char *fmt, ...)
va_start(ap, fmt);
early_printk("Kernel panic - not syncing: ");
early_vprintk(fmt, ap);
early_console->write(early_console, "\n", 1);
early_printk("\n");
va_end(ap);
dump_stack();
hv_halt();
}
static int __initdata keep_early;
static int __init setup_early_printk(char *str)
{
if (early_console)
return 1;
if (str != NULL && strncmp(str, "keep", 4) == 0)
keep_early = 1;
early_console = &early_hv_console;
register_console(early_console);
return 0;
}
void __init disable_early_printk(void)
{
early_console_complete = 1;
if (!early_console)
return;
if (!keep_early) {
early_printk("disabling early console\n");
unregister_console(early_console);
early_console = NULL;
} else {
early_printk("keeping early console\n");
}
}
void warn_early_printk(void)
{
if (early_console_complete || early_console)
return;
early_printk("\
Machine shutting down before console output is fully initialized.\n\
You may wish to reboot and add the option 'earlyprintk' to your\n\
boot command line to see any diagnostic early console output.\n\
");
}
early_param("earlyprintk", setup_early_printk);

View File

@ -56,4 +56,5 @@ hv_inquire_realpa = TEXT_OFFSET + 0x106c0;
hv_flush_all = TEXT_OFFSET + 0x106e0;
hv_get_ipi_pte = TEXT_OFFSET + 0x10700;
hv_set_pte_super_shift = TEXT_OFFSET + 0x10720;
hv_glue_internals = TEXT_OFFSET + 0x10740;
hv_console_set_ipi = TEXT_OFFSET + 0x107e0;
hv_glue_internals = TEXT_OFFSET + 0x10800;

View File

@ -27,7 +27,6 @@
void machine_halt(void)
{
warn_early_printk();
arch_local_irq_disable_all();
smp_send_stop();
hv_halt();
@ -35,7 +34,6 @@ void machine_halt(void)
void machine_power_off(void)
{
warn_early_printk();
arch_local_irq_disable_all();
smp_send_stop();
hv_power_off();

View File

@ -18,16 +18,46 @@
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/moduleparam.h>
#include <linux/platform_device.h>
#include <linux/types.h>
#include <asm/setup.h>
#include <arch/sim_def.h>
#include <hv/hypervisor.h>
#include "hvc_console.h"
static int use_sim_console;
static int __init sim_console(char *str)
{
use_sim_console = 1;
return 0;
}
early_param("sim_console", sim_console);
int tile_console_write(const char *buf, int count)
{
if (unlikely(use_sim_console)) {
int i;
for (i = 0; i < count; ++i)
__insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_PUTC |
(buf[i] << _SIM_CONTROL_OPERATOR_BITS));
__insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_PUTC |
(SIM_PUTC_FLUSH_BINARY <<
_SIM_CONTROL_OPERATOR_BITS));
return 0;
} else {
return hv_console_write((HV_VirtAddr)buf, count);
}
}
static int hvc_tile_put_chars(uint32_t vt, const char *buf, int count)
{
return hv_console_write((HV_VirtAddr)buf, count);
return tile_console_write(buf, count);
}
static int hvc_tile_get_chars(uint32_t vt, char *buf, int count)
@ -44,25 +74,132 @@ static int hvc_tile_get_chars(uint32_t vt, char *buf, int count)
return i;
}
#ifdef __tilegx__
/*
* IRQ based callbacks.
*/
static int hvc_tile_notifier_add_irq(struct hvc_struct *hp, int irq)
{
int rc;
int cpu = raw_smp_processor_id(); /* Choose an arbitrary cpu */
HV_Coord coord = { .x = cpu_x(cpu), .y = cpu_y(cpu) };
rc = notifier_add_irq(hp, irq);
if (rc)
return rc;
/*
* Request that the hypervisor start sending us interrupts.
* If the hypervisor returns an error, we still return 0, so that
* we can fall back to polling.
*/
if (hv_console_set_ipi(KERNEL_PL, irq, coord) < 0)
notifier_del_irq(hp, irq);
return 0;
}
static void hvc_tile_notifier_del_irq(struct hvc_struct *hp, int irq)
{
HV_Coord coord = { 0, 0 };
/* Tell the hypervisor to stop sending us interrupts. */
hv_console_set_ipi(KERNEL_PL, -1, coord);
notifier_del_irq(hp, irq);
}
static void hvc_tile_notifier_hangup_irq(struct hvc_struct *hp, int irq)
{
hvc_tile_notifier_del_irq(hp, irq);
}
#endif
static const struct hv_ops hvc_tile_get_put_ops = {
.get_chars = hvc_tile_get_chars,
.put_chars = hvc_tile_put_chars,
#ifdef __tilegx__
.notifier_add = hvc_tile_notifier_add_irq,
.notifier_del = hvc_tile_notifier_del_irq,
.notifier_hangup = hvc_tile_notifier_hangup_irq,
#endif
};
#ifdef __tilegx__
static int hvc_tile_probe(struct platform_device *pdev)
{
struct hvc_struct *hp;
int tile_hvc_irq;
/* Create our IRQ and register it. */
tile_hvc_irq = create_irq();
if (tile_hvc_irq < 0)
return -ENXIO;
tile_irq_activate(tile_hvc_irq, TILE_IRQ_PERCPU);
hp = hvc_alloc(0, tile_hvc_irq, &hvc_tile_get_put_ops, 128);
if (IS_ERR(hp)) {
destroy_irq(tile_hvc_irq);
return PTR_ERR(hp);
}
dev_set_drvdata(&pdev->dev, hp);
return 0;
}
static int hvc_tile_remove(struct platform_device *pdev)
{
int rc;
struct hvc_struct *hp = dev_get_drvdata(&pdev->dev);
rc = hvc_remove(hp);
if (rc == 0)
destroy_irq(hp->data);
return rc;
}
static void hvc_tile_shutdown(struct platform_device *pdev)
{
struct hvc_struct *hp = dev_get_drvdata(&pdev->dev);
hvc_tile_notifier_del_irq(hp, hp->data);
}
static struct platform_device hvc_tile_pdev = {
.name = "hvc-tile",
.id = 0,
};
static struct platform_driver hvc_tile_driver = {
.probe = hvc_tile_probe,
.remove = hvc_tile_remove,
.shutdown = hvc_tile_shutdown,
.driver = {
.name = "hvc-tile",
.owner = THIS_MODULE,
}
};
#endif
static int __init hvc_tile_console_init(void)
{
extern void disable_early_printk(void);
hvc_instantiate(0, 0, &hvc_tile_get_put_ops);
add_preferred_console("hvc", 0, NULL);
disable_early_printk();
return 0;
}
console_initcall(hvc_tile_console_init);
static int __init hvc_tile_init(void)
{
struct hvc_struct *s;
s = hvc_alloc(0, 0, &hvc_tile_get_put_ops, 128);
return IS_ERR(s) ? PTR_ERR(s) : 0;
#ifndef __tilegx__
struct hvc_struct *hp;
hp = hvc_alloc(0, 0, &hvc_tile_get_put_ops, 128);
return IS_ERR(hp) ? PTR_ERR(hp) : 0;
#else
platform_device_register(&hvc_tile_pdev);
return platform_driver_register(&hvc_tile_driver);
#endif
}
device_initcall(hvc_tile_init);