From bda0f5bad812df076a28fa5e58d86dfe68415251 Mon Sep 17 00:00:00 2001 From: Chris Metcalf Date: Tue, 6 Aug 2013 14:11:21 -0400 Subject: 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 Acked-by: Greg Kroah-Hartman --- drivers/tty/hvc/hvc_tile.c | 149 +++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 143 insertions(+), 6 deletions(-) (limited to 'drivers/tty/hvc') diff --git a/drivers/tty/hvc/hvc_tile.c b/drivers/tty/hvc/hvc_tile.c index 7a84a0595477..af8cdaa1dcb9 100644 --- a/drivers/tty/hvc/hvc_tile.c +++ b/drivers/tty/hvc/hvc_tile.c @@ -18,16 +18,46 @@ #include #include #include +#include +#include #include +#include #include +#include +#include + #include #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); -- cgit v1.2.3