From e95f287deed2454b8cad5b27859271db30130b2b Mon Sep 17 00:00:00 2001 From: Biwen Li Date: Mon, 2 Nov 2020 15:26:50 +0800 Subject: [PATCH] soc: fsl: handle RCPM errata A-008646 on SoC LS1021A Hardware issue: - Reading register RCPM_IPPDEXPCR1 always return zero, this causes system firmware could not get correct information and wrongly do clock gating for all wakeup source IP during system suspend. Then those IPs will never get chance to wake system. Workaround: - Copy register RCPM_IPPDEXPCR1's setting to register SCFG_SPARECR8 to allow system firmware's psci method read it and do things accordingly. Signed-off-by: Biwen Li Signed-off-by: Ran Wang Signed-off-by: Li Yang --- drivers/soc/fsl/rcpm.c | 35 ++++++++++++++++++++++++++++++++++- 1 file changed, 34 insertions(+), 1 deletion(-) diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c index a093dbe6d2cb..4ace28cab314 100644 --- a/drivers/soc/fsl/rcpm.c +++ b/drivers/soc/fsl/rcpm.c @@ -2,7 +2,7 @@ // // rcpm.c - Freescale QorIQ RCPM driver // -// Copyright 2019 NXP +// Copyright 2019-2020 NXP // // Author: Ran Wang @@ -22,6 +22,28 @@ struct rcpm { bool little_endian; }; +#define SCFG_SPARECR8 0x051c + +static void copy_ippdexpcr1_setting(u32 val) +{ + struct device_node *np; + void __iomem *regs; + u32 reg_val; + + np = of_find_compatible_node(NULL, NULL, "fsl,ls1021a-scfg"); + if (!np) + return; + + regs = of_iomap(np, 0); + if (!regs) + return; + + reg_val = ioread32be(regs + SCFG_SPARECR8); + iowrite32be(val | reg_val, regs + SCFG_SPARECR8); + + iounmap(regs); +} + /** * rcpm_pm_prepare - performs device-level tasks associated with power * management, such as programming related to the wakeup source control. @@ -90,6 +112,17 @@ static int rcpm_pm_prepare(struct device *dev) tmp |= ioread32be(address); iowrite32be(tmp, address); } + /* + * Workaround of errata A-008646 on SoC LS1021A: + * There is a bug of register ippdexpcr1. + * Reading configuration register RCPM_IPPDEXPCR1 + * always return zero. So save ippdexpcr1's value + * to register SCFG_SPARECR8.And the value of + * ippdexpcr1 will be read from SCFG_SPARECR8. + */ + if (dev_of_node(dev) && (i == 1)) + if (of_device_is_compatible(np, "fsl,ls1021a-rcpm")) + copy_ippdexpcr1_setting(tmp); } return 0;