Hi there! seems it's been three years since: [PATCH 1/1] Fix sprz319 erratum 2.1 http://article.gmane.org/gmane.linux.ports.arm.omap/71633 errata: http://www.ti.com/lit/er/sprz319f/sprz319f.pdf Nice summary (third post by Rodrigo Lemos) can be found here: https://github.com/RobertCNelson/stable-kernel/issues/26 so I'm not going to repeat it here. Company I'm working for has few thousands of IGEPv2 boards in field. They have hub connected to usb port with udlfb display, 3G modem and usbserial: /: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ehci-omap/3p, 480M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M |__ Port 1: Dev 3, If 0, Class=Vendor Specific Class, Driver=udlfb, 480M |__ Port 3: Dev 4, If 0, Class=Vendor Specific Class, Driver=option, 480M |__ Port 3: Dev 4, If 1, Class=Vendor Specific Class, Driver=, 480M |__ Port 3: Dev 4, If 2, Class=Vendor Specific Class, Driver=option, 480M |__ Port 3: Dev 4, If 3, Class=Vendor Specific Class, Driver=option, 480M |__ Port 3: Dev 4, If 4, Class=Mass Storage, Driver=usb-storage, 480M |__ Port 3: Dev 4, If 5, Class=Mass Storage, Driver=usb-storage, 480M |__ Port 4: Dev 5, If 0, Class=Hub, Driver=hub/4p, 480M |__ Port 3: Dev 6, If 0, Class=Communications, Driver=cdc_acm, 12M |__ Port 3: Dev 6, If 1, Class=CDC Data, Driver=cdc_acm, 12M Few tens of those disconnects USB after while (one minute to few hours) with: "usb usb3-port1: disabled by hub (EMI?), re-enabling..." IGEPv2 uses DM3730 with 26MHz crystal divided by two providing 13MHz SYS_CLK, therefore it is good candidate to fix. Patch bellow was used as a dirty hack to test if usb disconnects go away with errata applied. And indeed, device is already running for few days without any issues. Now question is, how should a proper fix look like as modifiing omap2_dpll_round_rate seems easy enough. Is that acceptable? How to test proper clock to apply errata? Comparing string is suboptimal. Should we introduce some flag? ladis --- linux-4.5/drivers/clk/ti/dpll3xxx.c.orig 2016-03-14 12:43:58.085003085 +0100 +++ linux-4.5/drivers/clk/ti/dpll3xxx.c 2016-03-14 13:17:57.893417000 +0100 @@ -308,6 +308,7 @@ u8 dco, sd_div, ai = 0; u32 v; bool errata_i810; + const char *clk_name; /* 3430 ES2 TRM: 4.7.6.9 DPLL Programming Sequence */ _omap3_noncore_dpll_bypass(clk); @@ -370,6 +371,12 @@ } } + clk_name = clk_hw_get_name(&clk->hw); + if (strcmp(clk_name, "dpll5_ck") == 0) { + pr_info("fixing %s (%04lx), %06x -> 01bb05\n", clk_name, dd->mult_div1_reg, v); + v = 0x1bb05; + } + ti_clk_ll_ops->clk_writel(v, dd->mult_div1_reg); /* Set 4X multiplier and low-power mode */ --- linux-4.5/drivers/clk/ti/divider.c.orig 2016-03-14 12:44:06.509211022 +0100 +++ linux-4.5/drivers/clk/ti/divider.c 2016-03-14 13:18:21.793417000 +0100 @@ -215,6 +215,7 @@ struct clk_divider *divider; unsigned int div, value; u32 val; + const char *clk_name; if (!hw || !rate) return -EINVAL; @@ -234,6 +235,13 @@ val &= ~(div_mask(divider) << divider->shift); } val |= value << divider->shift; + + clk_name = clk_hw_get_name(hw); + if (strcmp(clk_name, "dpll5_m2_ck") == 0) { + pr_info("fixing %s (%04lx), %04x -> 0008\n", clk_name, divider->reg, val); + val = 8; + } + ti_clk_ll_ops->clk_writel(val, divider->reg); return 0; -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
