From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Faiz Abbas To: , , , , Subject: [PATCH v4 4/6] bus: ti-sysc: Add support for software reset Date: Thu, 5 Jul 2018 19:53:17 +0530 Message-ID: <20180705142319.19583-5-faiz_abbas@ti.com> In-Reply-To: <20180705142319.19583-1-faiz_abbas@ti.com> References: <20180705142319.19583-1-faiz_abbas@ti.com> MIME-Version: 1.0 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, paul@pwsan.com, tony@atomide.com, faiz_abbas@ti.com, t-kristo@ti.com, robh+dt@kernel.org, bcousson@baylibre.com Content-Type: text/plain; charset="us-ascii" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+mturquette=baylibre.com@lists.infradead.org List-ID: Add support for the software reset of a target interconnect module using its sysconfig and sysstatus registers. Signed-off-by: Faiz Abbas --- drivers/bus/ti-sysc.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c index ad1cd6888757..ac65a4f336d5 100644 --- a/drivers/bus/ti-sysc.c +++ b/drivers/bus/ti-sysc.c @@ -23,11 +23,14 @@ #include #include #include +#include #include #include +#define MAX_MODULE_SOFTRESET_WAIT 10000 + static const char * const reg_names[] = { "rev", "sysc", "syss", }; enum sysc_clocks { @@ -88,6 +91,11 @@ struct sysc { struct delayed_work idle_work; }; +void sysc_write(struct sysc *ddata, int offset, u32 value) +{ + writel_relaxed(value, ddata->module_va + offset); +} + static u32 sysc_read(struct sysc *ddata, int offset) { if (ddata->cfg.quirks & SYSC_QUIRK_16BIT) { @@ -943,6 +951,26 @@ static void sysc_init_revision_quirks(struct sysc *ddata) } } +static int sysc_reset(struct sysc *ddata) +{ + int offset = ddata->offsets[SYSC_SYSCONFIG]; + int val = sysc_read(ddata, offset); + + val |= (0x1 << ddata->cap->regbits->srst_shift); + sysc_write(ddata, offset, val); + + /* Poll on reset status */ + if (ddata->cfg.syss_mask) { + offset = ddata->offsets[SYSC_SYSSTATUS]; + + return readl_poll_timeout(ddata->module_va + offset, val, + (val & ddata->cfg.syss_mask) == 0x0, + 100, MAX_MODULE_SOFTRESET_WAIT); + } + + return 0; +} + /* At this point the module is configured enough to read the revision */ static int sysc_init_module(struct sysc *ddata) { @@ -960,6 +988,17 @@ static int sysc_init_module(struct sysc *ddata) return 0; } + if (!(ddata->cfg.quirks & SYSC_QUIRK_NO_RESET_ON_INIT) && + !ddata->legacy_mode) { + error = sysc_reset(ddata); + if (error) { + dev_err(ddata->dev, "Reset failed with %d\n", error); + pm_runtime_put_sync(ddata->dev); + + return error; + } + } + ddata->revision = sysc_read_revision(ddata); pm_runtime_put_sync(ddata->dev); -- 2.17.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel