| Message ID | 20201202051634.490-1-wangzhiqiang.bj@bytedance.com |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | [1/2] misc: Add clock control logic into Aspeed LPC SNOOP driver | expand |
On Wed, 2 Dec 2020 at 05:16, John Wang <wangzhiqiang.bj@bytedance.com> wrote: > > From: Jae Hyun Yoo <jae.hyun.yoo@intel.com> > > If LPC SNOOP driver is registered ahead of lpc-ctrl module, LPC > SNOOP block will be enabled without heart beating of LCLK until > lpc-ctrl enables the LCLK. This issue causes improper handling on > host interrupts when the host sends interrupt in that time frame. > Then kernel eventually forcibly disables the interrupt with > dumping stack and printing a 'nobody cared this irq' message out. > > To prevent this issue, all LPC sub-nodes should enable LCLK > individually so this patch adds clock control logic into the LPC > SNOOP driver. > > Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@intel.com> > Signed-off-by: Vernon Mauery <vernon.mauery@linux.intel.com> > Signed-off-by: John Wang <wangzhiqiang.bj@bytedance.com> Reviewed-by: Joel Stanley <joel@jms.id.au> Thanks for sending these John. It is an excellent idea to upstream fixes that have been developed. I assume we will have the same issue for all devices that use the LPC bus? eg. vuart, bt, kcs, lpc2ahb? It looks like only the lpc-ctrl (lpc2ahb) does this so far: git grep -l clk drivers/soc/aspeed/aspeed-p2a-ctrl.c drivers/soc/aspeed/aspeed-lpc-ctrl.c drivers/char/ipmi/kcs_bmc_aspeed.c drivers/char/ipmi/bt-bmc.c drivers/soc/aspeed/aspeed-lpc-ctrl.c > --- > drivers/soc/aspeed/aspeed-lpc-snoop.c | 30 ++++++++++++++++++++++++--- > 1 file changed, 27 insertions(+), 3 deletions(-) > > diff --git a/drivers/soc/aspeed/aspeed-lpc-snoop.c b/drivers/soc/aspeed/aspeed-lpc-snoop.c > index 682ba0eb4eba..20acac6342ef 100644 > --- a/drivers/soc/aspeed/aspeed-lpc-snoop.c > +++ b/drivers/soc/aspeed/aspeed-lpc-snoop.c > @@ -11,6 +11,7 @@ > */ > > #include <linux/bitops.h> > +#include <linux/clk.h> > #include <linux/interrupt.h> > #include <linux/fs.h> > #include <linux/kfifo.h> > @@ -67,6 +68,7 @@ struct aspeed_lpc_snoop_channel { > struct aspeed_lpc_snoop { > struct regmap *regmap; > int irq; > + struct clk *clk; > struct aspeed_lpc_snoop_channel chan[NUM_SNOOP_CHANNELS]; > }; > > @@ -282,22 +284,42 @@ static int aspeed_lpc_snoop_probe(struct platform_device *pdev) > return -ENODEV; > } > > + lpc_snoop->clk = devm_clk_get(dev, NULL); > + if (IS_ERR(lpc_snoop->clk)) { > + rc = PTR_ERR(lpc_snoop->clk); > + if (rc != -EPROBE_DEFER) > + dev_err(dev, "couldn't get clock\n"); > + return rc; > + } > + rc = clk_prepare_enable(lpc_snoop->clk); > + if (rc) { > + dev_err(dev, "couldn't enable clock\n"); > + return rc; > + } > + > rc = aspeed_lpc_snoop_config_irq(lpc_snoop, pdev); > if (rc) > - return rc; > + goto err; > > rc = aspeed_lpc_enable_snoop(lpc_snoop, dev, 0, port); > if (rc) > - return rc; > + goto err; > > /* Configuration of 2nd snoop channel port is optional */ > if (of_property_read_u32_index(dev->of_node, "snoop-ports", > 1, &port) == 0) { > rc = aspeed_lpc_enable_snoop(lpc_snoop, dev, 1, port); > - if (rc) > + if (rc) { > aspeed_lpc_disable_snoop(lpc_snoop, 0); > + goto err; > + } > } > > + return 0; > + > +err: > + clk_disable_unprepare(lpc_snoop->clk); > + > return rc; > } > > @@ -309,6 +331,8 @@ static int aspeed_lpc_snoop_remove(struct platform_device *pdev) > aspeed_lpc_disable_snoop(lpc_snoop, 0); > aspeed_lpc_disable_snoop(lpc_snoop, 1); > > + clk_disable_unprepare(lpc_snoop->clk); > + > return 0; > } > > -- > 2.25.1 >
On Tue, Dec 8, 2020 at 10:19 AM Joel Stanley <joel@jms.id.au> wrote: > > On Wed, 2 Dec 2020 at 05:16, John Wang <wangzhiqiang.bj@bytedance.com> wrote: > > > > From: Jae Hyun Yoo <jae.hyun.yoo@intel.com> > > > > If LPC SNOOP driver is registered ahead of lpc-ctrl module, LPC > > SNOOP block will be enabled without heart beating of LCLK until > > lpc-ctrl enables the LCLK. This issue causes improper handling on > > host interrupts when the host sends interrupt in that time frame. > > Then kernel eventually forcibly disables the interrupt with > > dumping stack and printing a 'nobody cared this irq' message out. > > > > To prevent this issue, all LPC sub-nodes should enable LCLK > > individually so this patch adds clock control logic into the LPC > > SNOOP driver. > > > > Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@intel.com> > > Signed-off-by: Vernon Mauery <vernon.mauery@linux.intel.com> > > Signed-off-by: John Wang <wangzhiqiang.bj@bytedance.com> > > Reviewed-by: Joel Stanley <joel@jms.id.au> > > Thanks for sending these John. It is an excellent idea to upstream > fixes that have been developed. > > I assume we will have the same issue for all devices that use the LPC > bus? eg. vuart, bt, kcs, lpc2ahb? It looks like only the lpc-ctrl > (lpc2ahb) does this so far: ok that's on my todo list. :) > > git grep -l clk drivers/soc/aspeed/aspeed-p2a-ctrl.c > drivers/soc/aspeed/aspeed-lpc-ctrl.c > drivers/char/ipmi/kcs_bmc_aspeed.c drivers/char/ipmi/bt-bmc.c > drivers/soc/aspeed/aspeed-lpc-ctrl.c > > > > > > --- > > drivers/soc/aspeed/aspeed-lpc-snoop.c | 30 ++++++++++++++++++++++++--- > > 1 file changed, 27 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/soc/aspeed/aspeed-lpc-snoop.c b/drivers/soc/aspeed/aspeed-lpc-snoop.c > > index 682ba0eb4eba..20acac6342ef 100644 > > --- a/drivers/soc/aspeed/aspeed-lpc-snoop.c > > +++ b/drivers/soc/aspeed/aspeed-lpc-snoop.c > > @@ -11,6 +11,7 @@ > > */ > > > > #include <linux/bitops.h> > > +#include <linux/clk.h> > > #include <linux/interrupt.h> > > #include <linux/fs.h> > > #include <linux/kfifo.h> > > @@ -67,6 +68,7 @@ struct aspeed_lpc_snoop_channel { > > struct aspeed_lpc_snoop { > > struct regmap *regmap; > > int irq; > > + struct clk *clk; > > struct aspeed_lpc_snoop_channel chan[NUM_SNOOP_CHANNELS]; > > }; > > > > @@ -282,22 +284,42 @@ static int aspeed_lpc_snoop_probe(struct platform_device *pdev) > > return -ENODEV; > > } > > > > + lpc_snoop->clk = devm_clk_get(dev, NULL); > > + if (IS_ERR(lpc_snoop->clk)) { > > + rc = PTR_ERR(lpc_snoop->clk); > > + if (rc != -EPROBE_DEFER) > > + dev_err(dev, "couldn't get clock\n"); > > + return rc; > > + } > > + rc = clk_prepare_enable(lpc_snoop->clk); > > + if (rc) { > > + dev_err(dev, "couldn't enable clock\n"); > > + return rc; > > + } > > + > > rc = aspeed_lpc_snoop_config_irq(lpc_snoop, pdev); > > if (rc) > > - return rc; > > + goto err; > > > > rc = aspeed_lpc_enable_snoop(lpc_snoop, dev, 0, port); > > if (rc) > > - return rc; > > + goto err; > > > > /* Configuration of 2nd snoop channel port is optional */ > > if (of_property_read_u32_index(dev->of_node, "snoop-ports", > > 1, &port) == 0) { > > rc = aspeed_lpc_enable_snoop(lpc_snoop, dev, 1, port); > > - if (rc) > > + if (rc) { > > aspeed_lpc_disable_snoop(lpc_snoop, 0); > > + goto err; > > + } > > } > > > > + return 0; > > + > > +err: > > + clk_disable_unprepare(lpc_snoop->clk); > > + > > return rc; > > } > > > > @@ -309,6 +331,8 @@ static int aspeed_lpc_snoop_remove(struct platform_device *pdev) > > aspeed_lpc_disable_snoop(lpc_snoop, 0); > > aspeed_lpc_disable_snoop(lpc_snoop, 1); > > > > + clk_disable_unprepare(lpc_snoop->clk); > > + > > return 0; > > } > > > > -- > > 2.25.1 > >
diff --git a/drivers/soc/aspeed/aspeed-lpc-snoop.c b/drivers/soc/aspeed/aspeed-lpc-snoop.c index 682ba0eb4eba..20acac6342ef 100644 --- a/drivers/soc/aspeed/aspeed-lpc-snoop.c +++ b/drivers/soc/aspeed/aspeed-lpc-snoop.c @@ -11,6 +11,7 @@ */ #include <linux/bitops.h> +#include <linux/clk.h> #include <linux/interrupt.h> #include <linux/fs.h> #include <linux/kfifo.h> @@ -67,6 +68,7 @@ struct aspeed_lpc_snoop_channel { struct aspeed_lpc_snoop { struct regmap *regmap; int irq; + struct clk *clk; struct aspeed_lpc_snoop_channel chan[NUM_SNOOP_CHANNELS]; }; @@ -282,22 +284,42 @@ static int aspeed_lpc_snoop_probe(struct platform_device *pdev) return -ENODEV; } + lpc_snoop->clk = devm_clk_get(dev, NULL); + if (IS_ERR(lpc_snoop->clk)) { + rc = PTR_ERR(lpc_snoop->clk); + if (rc != -EPROBE_DEFER) + dev_err(dev, "couldn't get clock\n"); + return rc; + } + rc = clk_prepare_enable(lpc_snoop->clk); + if (rc) { + dev_err(dev, "couldn't enable clock\n"); + return rc; + } + rc = aspeed_lpc_snoop_config_irq(lpc_snoop, pdev); if (rc) - return rc; + goto err; rc = aspeed_lpc_enable_snoop(lpc_snoop, dev, 0, port); if (rc) - return rc; + goto err; /* Configuration of 2nd snoop channel port is optional */ if (of_property_read_u32_index(dev->of_node, "snoop-ports", 1, &port) == 0) { rc = aspeed_lpc_enable_snoop(lpc_snoop, dev, 1, port); - if (rc) + if (rc) { aspeed_lpc_disable_snoop(lpc_snoop, 0); + goto err; + } } + return 0; + +err: + clk_disable_unprepare(lpc_snoop->clk); + return rc; } @@ -309,6 +331,8 @@ static int aspeed_lpc_snoop_remove(struct platform_device *pdev) aspeed_lpc_disable_snoop(lpc_snoop, 0); aspeed_lpc_disable_snoop(lpc_snoop, 1); + clk_disable_unprepare(lpc_snoop->clk); + return 0; }