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authorArnd Bergmann <arnd@arndb.de>2021-01-18 12:45:46 +0100
committerArnd Bergmann <arnd@arndb.de>2021-01-20 09:30:45 +0100
commita579fcfa8e49cc77ad59211bb18bc5004133e6a0 (patch)
tree51eee55987ddb1fdd125922606b71bafdf3b9bb8 /arch/c6x/platforms/timer64.c
parentbd97ad35e816daf9a72ee35d3524d8417f7cf414 (diff)
c6x: remove architecture
The c6x architecture was added to the kernel in 2011 at a time when running Linux on DSPs was widely seen as the logical evolution. It appears the trend has gone back to running Linux on Arm based SoCs with DSP, using a better supported software ecosystem, and having better real-time behavior for the DSP code. An example of this is TI's own Keystone2 platform. The upstream kernel port appears to no longer have any users. Mark Salter remained avaialable to review patches, but mentioned that he no longer has access to working hardware himself. Without any users, it's best to just remove the code completely to reduce the work for cross-architecture code changes. Many thanks to Mark for maintaining the code for the past ten years. Link: https://lore.kernel.org/lkml/41dc7795afda9f776d8cd0d3075f776cf586e97c.camel@redhat.com/ Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/c6x/platforms/timer64.c')
-rw-r--r--arch/c6x/platforms/timer64.c241
1 files changed, 0 insertions, 241 deletions
diff --git a/arch/c6x/platforms/timer64.c b/arch/c6x/platforms/timer64.c
deleted file mode 100644
index 661f4c7c6ef6..000000000000
--- a/arch/c6x/platforms/timer64.c
+++ /dev/null
@@ -1,241 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (C) 2010, 2011 Texas Instruments Incorporated
- * Contributed by: Mark Salter (msalter@redhat.com)
- */
-
-#include <linux/clockchips.h>
-#include <linux/interrupt.h>
-#include <linux/io.h>
-#include <linux/of.h>
-#include <linux/of_irq.h>
-#include <linux/of_address.h>
-#include <asm/soc.h>
-#include <asm/dscr.h>
-#include <asm/special_insns.h>
-#include <asm/timer64.h>
-
-struct timer_regs {
- u32 reserved0;
- u32 emumgt;
- u32 reserved1;
- u32 reserved2;
- u32 cntlo;
- u32 cnthi;
- u32 prdlo;
- u32 prdhi;
- u32 tcr;
- u32 tgcr;
- u32 wdtcr;
-};
-
-static struct timer_regs __iomem *timer;
-
-#define TCR_TSTATLO 0x001
-#define TCR_INVOUTPLO 0x002
-#define TCR_INVINPLO 0x004
-#define TCR_CPLO 0x008
-#define TCR_ENAMODELO_ONCE 0x040
-#define TCR_ENAMODELO_CONT 0x080
-#define TCR_ENAMODELO_MASK 0x0c0
-#define TCR_PWIDLO_MASK 0x030
-#define TCR_CLKSRCLO 0x100
-#define TCR_TIENLO 0x200
-#define TCR_TSTATHI (0x001 << 16)
-#define TCR_INVOUTPHI (0x002 << 16)
-#define TCR_CPHI (0x008 << 16)
-#define TCR_PWIDHI_MASK (0x030 << 16)
-#define TCR_ENAMODEHI_ONCE (0x040 << 16)
-#define TCR_ENAMODEHI_CONT (0x080 << 16)
-#define TCR_ENAMODEHI_MASK (0x0c0 << 16)
-
-#define TGCR_TIMLORS 0x001
-#define TGCR_TIMHIRS 0x002
-#define TGCR_TIMMODE_UD32 0x004
-#define TGCR_TIMMODE_WDT64 0x008
-#define TGCR_TIMMODE_CD32 0x00c
-#define TGCR_TIMMODE_MASK 0x00c
-#define TGCR_PSCHI_MASK (0x00f << 8)
-#define TGCR_TDDRHI_MASK (0x00f << 12)
-
-/*
- * Timer clocks are divided down from the CPU clock
- * The divisor is in the EMUMGTCLKSPD register
- */
-#define TIMER_DIVISOR \
- ((soc_readl(&timer->emumgt) & (0xf << 16)) >> 16)
-
-#define TIMER64_RATE (c6x_core_freq / TIMER_DIVISOR)
-
-#define TIMER64_MODE_DISABLED 0
-#define TIMER64_MODE_ONE_SHOT TCR_ENAMODELO_ONCE
-#define TIMER64_MODE_PERIODIC TCR_ENAMODELO_CONT
-
-static int timer64_mode;
-static int timer64_devstate_id = -1;
-
-static void timer64_config(unsigned long period)
-{
- u32 tcr = soc_readl(&timer->tcr) & ~TCR_ENAMODELO_MASK;
-
- soc_writel(tcr, &timer->tcr);
- soc_writel(period - 1, &timer->prdlo);
- soc_writel(0, &timer->cntlo);
- tcr |= timer64_mode;
- soc_writel(tcr, &timer->tcr);
-}
-
-static void timer64_enable(void)
-{
- u32 val;
-
- if (timer64_devstate_id >= 0)
- dscr_set_devstate(timer64_devstate_id, DSCR_DEVSTATE_ENABLED);
-
- /* disable timer, reset count */
- soc_writel(soc_readl(&timer->tcr) & ~TCR_ENAMODELO_MASK, &timer->tcr);
- soc_writel(0, &timer->prdlo);
-
- /* use internal clock and 1 cycle pulse width */
- val = soc_readl(&timer->tcr);
- soc_writel(val & ~(TCR_CLKSRCLO | TCR_PWIDLO_MASK), &timer->tcr);
-
- /* dual 32-bit unchained mode */
- val = soc_readl(&timer->tgcr) & ~TGCR_TIMMODE_MASK;
- soc_writel(val, &timer->tgcr);
- soc_writel(val | (TGCR_TIMLORS | TGCR_TIMMODE_UD32), &timer->tgcr);
-}
-
-static void timer64_disable(void)
-{
- /* disable timer, reset count */
- soc_writel(soc_readl(&timer->tcr) & ~TCR_ENAMODELO_MASK, &timer->tcr);
- soc_writel(0, &timer->prdlo);
-
- if (timer64_devstate_id >= 0)
- dscr_set_devstate(timer64_devstate_id, DSCR_DEVSTATE_DISABLED);
-}
-
-static int next_event(unsigned long delta,
- struct clock_event_device *evt)
-{
- timer64_config(delta);
- return 0;
-}
-
-static int set_periodic(struct clock_event_device *evt)
-{
- timer64_enable();
- timer64_mode = TIMER64_MODE_PERIODIC;
- timer64_config(TIMER64_RATE / HZ);
- return 0;
-}
-
-static int set_oneshot(struct clock_event_device *evt)
-{
- timer64_enable();
- timer64_mode = TIMER64_MODE_ONE_SHOT;
- return 0;
-}
-
-static int shutdown(struct clock_event_device *evt)
-{
- timer64_mode = TIMER64_MODE_DISABLED;
- timer64_disable();
- return 0;
-}
-
-static struct clock_event_device t64_clockevent_device = {
- .name = "TIMER64_EVT32_TIMER",
- .features = CLOCK_EVT_FEAT_ONESHOT |
- CLOCK_EVT_FEAT_PERIODIC,
- .rating = 200,
- .set_state_shutdown = shutdown,
- .set_state_periodic = set_periodic,
- .set_state_oneshot = set_oneshot,
- .set_next_event = next_event,
-};
-
-static irqreturn_t timer_interrupt(int irq, void *dev_id)
-{
- struct clock_event_device *cd = &t64_clockevent_device;
-
- cd->event_handler(cd);
-
- return IRQ_HANDLED;
-}
-
-void __init timer64_init(void)
-{
- struct clock_event_device *cd = &t64_clockevent_device;
- struct device_node *np, *first = NULL;
- u32 val;
- int err, found = 0;
-
- for_each_compatible_node(np, NULL, "ti,c64x+timer64") {
- err = of_property_read_u32(np, "ti,core-mask", &val);
- if (!err) {
- if (val & (1 << get_coreid())) {
- found = 1;
- break;
- }
- } else if (!first)
- first = np;
- }
- if (!found) {
- /* try first one with no core-mask */
- if (first)
- np = of_node_get(first);
- else {
- pr_debug("Cannot find ti,c64x+timer64 timer.\n");
- return;
- }
- }
-
- timer = of_iomap(np, 0);
- if (!timer) {
- pr_debug("%pOF: Cannot map timer registers.\n", np);
- goto out;
- }
- pr_debug("%pOF: Timer registers=%p.\n", np, timer);
-
- cd->irq = irq_of_parse_and_map(np, 0);
- if (cd->irq == NO_IRQ) {
- pr_debug("%pOF: Cannot find interrupt.\n", np);
- iounmap(timer);
- goto out;
- }
-
- /* If there is a device state control, save the ID. */
- err = of_property_read_u32(np, "ti,dscr-dev-enable", &val);
- if (!err) {
- timer64_devstate_id = val;
-
- /*
- * It is necessary to enable the timer block here because
- * the TIMER_DIVISOR macro needs to read a timer register
- * to get the divisor.
- */
- dscr_set_devstate(timer64_devstate_id, DSCR_DEVSTATE_ENABLED);
- }
-
- pr_debug("%pOF: Timer irq=%d.\n", np, cd->irq);
-
- clockevents_calc_mult_shift(cd, c6x_core_freq / TIMER_DIVISOR, 5);
-
- cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd);
- cd->max_delta_ticks = 0x7fffffff;
- cd->min_delta_ns = clockevent_delta2ns(250, cd);
- cd->min_delta_ticks = 250;
-
- cd->cpumask = cpumask_of(smp_processor_id());
-
- clockevents_register_device(cd);
- if (request_irq(cd->irq, timer_interrupt, IRQF_TIMER, "timer",
- &t64_clockevent_device))
- pr_err("Failed to request irq %d (timer)\n", cd->irq);
-
-out:
- of_node_put(np);
- return;
-}