| Message ID | 20200124132957.15769-3-geert+renesas@glider.be |
|---|---|
| State | New |
| Headers | show |
| Series | Fix debugfs register access while suspended | expand |
diff --git a/drivers/crypto/ccree/cc_debugfs.c b/drivers/crypto/ccree/cc_debugfs.c index 5669997386988055..35f3a2137502bd96 100644 --- a/drivers/crypto/ccree/cc_debugfs.c +++ b/drivers/crypto/ccree/cc_debugfs.c @@ -81,6 +81,7 @@ int cc_debugfs_init(struct cc_drvdata *drvdata) regset->regs = debug_regs; regset->nregs = ARRAY_SIZE(debug_regs); regset->base = drvdata->cc_base; + regset->dev = dev; ctx->dir = debugfs_create_dir(drvdata->plat_dev->name, cc_debugfs_dir); @@ -102,6 +103,7 @@ int cc_debugfs_init(struct cc_drvdata *drvdata) verset->nregs = ARRAY_SIZE(pid_cid_regs); } verset->base = drvdata->cc_base; + verset->dev = dev; debugfs_create_regset32("version", 0400, ctx->dir, verset);
Reading the debugfs files under /sys/kernel/debug/ccree/ can be done by the user at any time. On R-Car SoCs, the CCREE device is power-managed using a moduile clock, and if this clock is not running, bogus register values may be read. Fix this by filling in the debugfs_regset32.dev field, so debugfs will make sure the device is resumed while its registers are being read. This fixes the bogus values (0x00000260) in the register dumps on R-Car H3 ES1.0: -e6601000.crypto/regs:HOST_IRR = 0x00000260 -e6601000.crypto/regs:HOST_POWER_DOWN_EN = 0x00000260 +e6601000.crypto/regs:HOST_IRR = 0x00000038 +e6601000.crypto/regs:HOST_POWER_DOWN_EN = 0x00000038 e6601000.crypto/regs:AXIM_MON_ERR = 0x00000000 e6601000.crypto/regs:DSCRPTR_QUEUE_CONTENT = 0x000002aa -e6601000.crypto/regs:HOST_IMR = 0x00000260 +e6601000.crypto/regs:HOST_IMR = 0x017ffeff e6601000.crypto/regs:AXIM_CFG = 0x001f0007 e6601000.crypto/regs:AXIM_CACHE_PARAMS = 0x00000000 -e6601000.crypto/regs:GPR_HOST = 0x00000260 +e6601000.crypto/regs:GPR_HOST = 0x017ffeff e6601000.crypto/regs:AXIM_MON_COMP = 0x00000000 -e6601000.crypto/version:SIGNATURE = 0x00000260 -e6601000.crypto/version:VERSION = 0x00000260 +e6601000.crypto/version:SIGNATURE = 0xdcc63000 +e6601000.crypto/version:VERSION = 0xaf400001 Note that this behavior is system-dependent, and the issue does not show up on all R-Car Gen3 SoCs and boards. Even when the device is suspended, the module clock may be left enabled, if configured by the firmware for Secure Mode, or when controlled by the Real-Time Core. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> --- drivers/crypto/ccree/cc_debugfs.c | 2 ++ 1 file changed, 2 insertions(+)