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authorSuman Anna <s-anna@ti.com>2020-02-28 01:28:34 +0300
committerTony Lindgren <tony@atomide.com>2020-03-04 18:54:57 +0300
commitb2745d92bb015cc4454d4195c4ce6e2852db397e (patch)
tree65fd7d7a183b2520e2d6bc29484430e7b4320f62 /drivers/bus
parent4d0dd3802ee1b6b14b7c46621cd581eb7c1ade79 (diff)
downloadlinux-b2745d92bb015cc4454d4195c4ce6e2852db397e.tar.xz
bus: ti-sysc: Add support for PRUSS SYSC type
The PRU-ICSS present on AM33xx/AM43xx/AM57xx has a very unique SYSCFG register. The register follows the OMAP4-style SYSC_TYPE3 for Master Standby and Slave Idle, but also has two additional unique fields - STANDBY_INIT and SUB_MWAIT. The STANDBY_INIT is a control bit that is used to initiate a Standby sequence (when set) and trigger a MStandby request to the SoC's PRCM module. This same bit is also used to enable the OCP master ports (when cleared) to allow the PRU cores to access any peripherals or memory beyond the PRU subsystem. The SUB_MWAIT is a ready status field for the external access. Add support for this SYSC type. The STANDBY_INIT has to be set during suspend, without which it results in a hang in the resume sequence on AM33xx/AM43xx boards and requires a board reset to come out of the hang. Any PRU applications requiring external access are supposed to clear the STANDBY_INIT bit. Note that the PRUSS context is lost during a suspend sequence because the PRUSS module is reset and/or disabled. Signed-off-by: Suman Anna <s-anna@ti.com> Signed-off-by: Roger Quadros <rogerq@ti.com> [tony@atomide.com: updated quirk define number and to use -ENODEV] Signed-off-by: Tony Lindgren <tony@atomide.com>
Diffstat (limited to 'drivers/bus')
-rw-r--r--drivers/bus/ti-sysc.c27
1 files changed, 27 insertions, 0 deletions
diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
index bc1c52f87046..86ac61fa5bc6 100644
--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -1341,6 +1341,9 @@ static const struct sysc_revision_quirk sysc_revision_quirks[] = {
SYSC_QUIRK_SWSUP_SIDLE | SYSC_QUIRK_SWSUP_MSTANDBY),
SYSC_QUIRK("wdt", 0, 0, 0x10, 0x14, 0x502a0500, 0xfffff0f0,
SYSC_MODULE_QUIRK_WDT),
+ /* PRUSS on am3, am4 and am5 */
+ SYSC_QUIRK("pruss", 0, 0x26000, 0x26004, -ENODEV, 0x47000000, 0xff000000,
+ SYSC_MODULE_QUIRK_PRUSS),
/* Watchdog on am3 and am4 */
SYSC_QUIRK("wdt", 0x44e35000, 0, 0x10, 0x14, 0x502a0500, 0xfffff0f0,
SYSC_MODULE_QUIRK_WDT | SYSC_QUIRK_SWSUP_SIDLE),
@@ -1712,6 +1715,16 @@ static void sysc_reset_done_quirk_wdt(struct sysc *ddata)
dev_warn(ddata->dev, "wdt disable step2 failed\n");
}
+/* PRUSS needs to set MSTANDBY_INIT inorder to idle properly */
+static void sysc_module_disable_quirk_pruss(struct sysc *ddata)
+{
+ u32 reg;
+
+ reg = sysc_read(ddata, ddata->offsets[SYSC_SYSCONFIG]);
+ reg |= SYSC_PRUSS_STANDBY_INIT;
+ sysc_write(ddata, ddata->offsets[SYSC_SYSCONFIG], reg);
+}
+
static void sysc_init_module_quirks(struct sysc *ddata)
{
if (ddata->legacy_mode || !ddata->name)
@@ -1750,6 +1763,9 @@ static void sysc_init_module_quirks(struct sysc *ddata)
ddata->reset_done_quirk = sysc_reset_done_quirk_wdt;
ddata->module_disable_quirk = sysc_reset_done_quirk_wdt;
}
+
+ if (ddata->cfg.quirks & SYSC_MODULE_QUIRK_PRUSS)
+ ddata->module_disable_quirk = sysc_module_disable_quirk_pruss;
}
static int sysc_clockdomain_init(struct sysc *ddata)
@@ -2555,6 +2571,16 @@ static const struct sysc_capabilities sysc_dra7_mcan = {
.mod_quirks = SYSS_QUIRK_RESETDONE_INVERTED,
};
+/*
+ * PRUSS found on some AM33xx, AM437x and AM57xx SoCs
+ */
+static const struct sysc_capabilities sysc_pruss = {
+ .type = TI_SYSC_PRUSS,
+ .sysc_mask = SYSC_PRUSS_STANDBY_INIT | SYSC_PRUSS_SUB_MWAIT,
+ .regbits = &sysc_regbits_omap4_simple,
+ .mod_quirks = SYSC_MODULE_QUIRK_PRUSS,
+};
+
static int sysc_init_pdata(struct sysc *ddata)
{
struct ti_sysc_platform_data *pdata = dev_get_platdata(ddata->dev);
@@ -2936,6 +2962,7 @@ static const struct of_device_id sysc_match[] = {
{ .compatible = "ti,sysc-usb-host-fs",
.data = &sysc_omap4_usb_host_fs, },
{ .compatible = "ti,sysc-dra7-mcan", .data = &sysc_dra7_mcan, },
+ { .compatible = "ti,sysc-pruss", .data = &sysc_pruss, },
{ },
};
MODULE_DEVICE_TABLE(of, sysc_match);