From 1da39ff09e561df9062342563ce8db9b9181a3de Mon Sep 17 00:00:00 2001 From: Pawel Dembicki Date: Fri, 5 Jul 2019 00:29:07 +0200 Subject: [PATCH] net: dsa: vsc73xx: Assert reset if iCPU is enabled Driver allow to use devices with disabled iCPU only. Some devices have pre-initialised iCPU by bootloader. That state make switch unmanaged. This patch force reset if device is in unmanaged state. In the result chip lost internal firmware from RAM and it can be managed. Signed-off-by: Pawel Dembicki Reviewed-by: Linus Walleij Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/dsa/vitesse-vsc73xx-core.c | 36 ++++++++++++-------------- 1 file changed, 17 insertions(+), 19 deletions(-) diff --git a/drivers/net/dsa/vitesse-vsc73xx-core.c b/drivers/net/dsa/vitesse-vsc73xx-core.c index 10063f31d9a3..614377ef7956 100644 --- a/drivers/net/dsa/vitesse-vsc73xx-core.c +++ b/drivers/net/dsa/vitesse-vsc73xx-core.c @@ -417,22 +417,8 @@ static int vsc73xx_detect(struct vsc73xx *vsc) } if (val == 0xffffffff) { - dev_info(vsc->dev, "chip seems dead, assert reset\n"); - gpiod_set_value_cansleep(vsc->reset, 1); - /* Reset pulse should be 20ns minimum, according to datasheet - * table 245, so 10us should be fine - */ - usleep_range(10, 100); - gpiod_set_value_cansleep(vsc->reset, 0); - /* Wait 20ms according to datasheet table 245 */ - msleep(20); - - ret = vsc73xx_read(vsc, VSC73XX_BLOCK_SYSTEM, 0, - VSC73XX_ICPU_MBOX_VAL, &val); - if (val == 0xffffffff) { - dev_err(vsc->dev, "seems not to help, giving up\n"); - return -ENODEV; - } + dev_info(vsc->dev, "chip seems dead.\n"); + return -EAGAIN; } ret = vsc73xx_read(vsc, VSC73XX_BLOCK_SYSTEM, 0, @@ -483,9 +469,8 @@ static int vsc73xx_detect(struct vsc73xx *vsc) } if (icpu_si_boot_en && !icpu_pi_en) { dev_err(vsc->dev, - "iCPU enabled boots from SI, no external memory\n"); - dev_err(vsc->dev, "no idea how to deal with this\n"); - return -ENODEV; + "iCPU enabled boots from PI/SI, no external memory\n"); + return -EAGAIN; } if (!icpu_si_boot_en && icpu_pi_en) { dev_err(vsc->dev, @@ -1158,6 +1143,19 @@ int vsc73xx_probe(struct vsc73xx *vsc) msleep(20); ret = vsc73xx_detect(vsc); + if (ret == -EAGAIN) { + dev_err(vsc->dev, + "Chip seems to be out of control. Assert reset and try again.\n"); + gpiod_set_value_cansleep(vsc->reset, 1); + /* Reset pulse should be 20ns minimum, according to datasheet + * table 245, so 10us should be fine + */ + usleep_range(10, 100); + gpiod_set_value_cansleep(vsc->reset, 0); + /* Wait 20ms according to datasheet table 245 */ + msleep(20); + ret = vsc73xx_detect(vsc); + } if (ret) { dev_err(dev, "no chip found (%d)\n", ret); return -ENODEV;