From patchwork Thu Jul 25 23:52:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Piggin X-Patchwork-Id: 13742249 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BD0C3C3DA7F for ; Thu, 25 Jul 2024 23:55:42 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sX8JA-0007V1-64; Thu, 25 Jul 2024 19:55:40 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sX8Iy-0006ps-Fg; Thu, 25 Jul 2024 19:55:29 -0400 Received: from mail-pj1-x1029.google.com ([2607:f8b0:4864:20::1029]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1sX8Iw-0000uI-5K; Thu, 25 Jul 2024 19:55:28 -0400 Received: by mail-pj1-x1029.google.com with SMTP id 98e67ed59e1d1-2cb682fb0cdso290404a91.3; Thu, 25 Jul 2024 16:55:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1721951724; x=1722556524; darn=nongnu.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=v0qYWXQCi7Id5dm6kbS55QVjNxgYMe0vHIm8o971smw=; b=Ufieob0eW8mHO/uiq026QKRFooVo/goI8naDEtiu51EeIq+PctGZRRaa6RHE4Emrw8 aFK1w2X40I3m6AjsQ0ti+bsOfrbBIg/jlcjVcO2Z1tvZi9CZvshxNrHHS1ArYQYZQa54 9L1XI6R2unHyZe8mEA4dM3lm1KwqzXdeYB87YdCU4eUmi2/l0Fa2UjCWKPeI2S/sEiU/ c0X21bdHokkf8gm7D22PVVWSAB/crh2bgh+w+oKIWi8lfudQ1oxTUjSVnUZ1kOvOxvr2 ZNPpr1s30vjJ8wrImuwgSqXvLtEu9r8MvP2Bwtm1GCrOflRe/FfKHgjBucr6gCACLo13 28Uw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1721951724; x=1722556524; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=v0qYWXQCi7Id5dm6kbS55QVjNxgYMe0vHIm8o971smw=; b=l9Ehj408CZj3KenA31cpsSWUocY8PpNq4/iQPRZRHio+EICPdl001lOz6KoXcz97fQ WKXVxBi/VvaToBnZ4RpH8TuRPO57I10KWYct7hvKEWvgv0IzXkSCX/0l4qGWQhzZ1Q2Y Y5s8l0ZhPR7G2qQAT7+7r/VaMTYM//5QbMo9Y+2eXAY6Rzw/dSKlAHF1k02IQZEaSvho o6Ra6iPy9wd/W3smDNPyVMydfqP4QUJHvtpJ+jyPAQp+QHCCzX5WK0eL3AxnV7z44ptC Q6OR5mzcoKDZj2+1MOiTY+/xGUEbhHjmY1KXokzLl82jdihVSsdRo0FjRhW5GjeKQA0r duGA== X-Forwarded-Encrypted: i=1; AJvYcCWSkAh6/njmQxTWt1LKZ98EjeuOaIsiQp/sLxFQQxUvOOYnP59nX/nsWiJ+UF2EirD+yEPhQ2bkmwCwK7RvBGQHxUKI X-Gm-Message-State: AOJu0Yy7DHy+LsxuPLrdSRHtTySj37/4k4+vKOwHFKLyXDdz+oVJNaiv XVNL8/KkfGGFiE8eKpXUj2yqtrH9txkk2APvp1UOVr9fYHK3iQB0ZEtDUQ== X-Google-Smtp-Source: AGHT+IFJlOWuvSlYnTjdFNE/lbEqr2mqJfW5QJIZmNdGN66v13bUG5F9naDXVyFgkqBxikUvQ3bl7Q== X-Received: by 2002:a17:90b:4ad1:b0:2c7:f3de:27ef with SMTP id 98e67ed59e1d1-2cf23943778mr4847287a91.42.1721951723201; Thu, 25 Jul 2024 16:55:23 -0700 (PDT) Received: from wheely.local0.net ([203.220.44.216]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-2cf28c7fef3sm2142060a91.16.2024.07.25.16.55.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Jul 2024 16:55:22 -0700 (PDT) From: Nicholas Piggin To: qemu-devel@nongnu.org Cc: Nicholas Piggin , qemu-ppc@nongnu.org, Glenn Miles Subject: [PULL 15/96] ppc/pnv: Implement POWER9 LPC PSI serirq outputs and auto-clear function Date: Fri, 26 Jul 2024 09:52:48 +1000 Message-ID: <20240725235410.451624-16-npiggin@gmail.com> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240725235410.451624-1-npiggin@gmail.com> References: <20240725235410.451624-1-npiggin@gmail.com> MIME-Version: 1.0 Received-SPF: pass client-ip=2607:f8b0:4864:20::1029; envelope-from=npiggin@gmail.com; helo=mail-pj1-x1029.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org The POWER8 LPC ISA device irqs all get combined and reported to the line connected the PSI LPCHC irq. POWER9 changed this so only internal LPC host controller irqs use that line, and the device irqs get routed to 4 new lines connected to PSI SERIRQ0-3. POWER9 also introduced a new feature that automatically clears the irq status in the LPC host controller when EOI'ed, so software does not have to. The powernv OPAL (skiboot) firmware managed to work because the LPCHC irq handler scanned all LPC irqs and handled those including clearing status even on POWER9 systems. So LPC irqs worked despite OPAL thinking it was running in POWER9 mode. After this change, UART interrupts show up on serirq1 which is where OPAL routes them to: cat /proc/interrupts ... 20: 0 XIVE-IRQ 1048563 Level opal-psi#0:lpchc ... 25: 34 XIVE-IRQ 1048568 Level opal-psi#0:lpc_serirq_mux1 Whereas they previously turn up on lpchc. Reviewed-by: Glenn Miles Signed-off-by: Nicholas Piggin --- hw/ppc/pnv.c | 36 +++++++++-- hw/ppc/pnv_lpc.c | 128 ++++++++++++++++++++++++++++++++------- include/hw/ppc/pnv_lpc.h | 14 ++++- 3 files changed, 148 insertions(+), 30 deletions(-) diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c index 13cebd6ab9..f56dcf6597 100644 --- a/hw/ppc/pnv.c +++ b/hw/ppc/pnv.c @@ -727,7 +727,8 @@ static ISABus *pnv_chip_power8_isa_create(PnvChip *chip, Error **errp) Pnv8Chip *chip8 = PNV8_CHIP(chip); qemu_irq irq = qdev_get_gpio_in(DEVICE(&chip8->psi), PSIHB_IRQ_EXTERNAL); - qdev_connect_gpio_out(DEVICE(&chip8->lpc), 0, irq); + qdev_connect_gpio_out_named(DEVICE(&chip8->lpc), "LPCHC", 0, irq); + return pnv_lpc_isa_create(&chip8->lpc, true, errp); } @@ -736,25 +737,48 @@ static ISABus *pnv_chip_power8nvl_isa_create(PnvChip *chip, Error **errp) Pnv8Chip *chip8 = PNV8_CHIP(chip); qemu_irq irq = qdev_get_gpio_in(DEVICE(&chip8->psi), PSIHB_IRQ_LPC_I2C); - qdev_connect_gpio_out(DEVICE(&chip8->lpc), 0, irq); + qdev_connect_gpio_out_named(DEVICE(&chip8->lpc), "LPCHC", 0, irq); + return pnv_lpc_isa_create(&chip8->lpc, false, errp); } static ISABus *pnv_chip_power9_isa_create(PnvChip *chip, Error **errp) { Pnv9Chip *chip9 = PNV9_CHIP(chip); - qemu_irq irq = qdev_get_gpio_in(DEVICE(&chip9->psi), PSIHB9_IRQ_LPCHC); + qemu_irq irq; + + irq = qdev_get_gpio_in(DEVICE(&chip9->psi), PSIHB9_IRQ_LPCHC); + qdev_connect_gpio_out_named(DEVICE(&chip9->lpc), "LPCHC", 0, irq); + + irq = qdev_get_gpio_in(DEVICE(&chip9->psi), PSIHB9_IRQ_LPC_SIRQ0); + qdev_connect_gpio_out_named(DEVICE(&chip9->lpc), "SERIRQ", 0, irq); + irq = qdev_get_gpio_in(DEVICE(&chip9->psi), PSIHB9_IRQ_LPC_SIRQ1); + qdev_connect_gpio_out_named(DEVICE(&chip9->lpc), "SERIRQ", 1, irq); + irq = qdev_get_gpio_in(DEVICE(&chip9->psi), PSIHB9_IRQ_LPC_SIRQ2); + qdev_connect_gpio_out_named(DEVICE(&chip9->lpc), "SERIRQ", 2, irq); + irq = qdev_get_gpio_in(DEVICE(&chip9->psi), PSIHB9_IRQ_LPC_SIRQ3); + qdev_connect_gpio_out_named(DEVICE(&chip9->lpc), "SERIRQ", 3, irq); - qdev_connect_gpio_out(DEVICE(&chip9->lpc), 0, irq); return pnv_lpc_isa_create(&chip9->lpc, false, errp); } static ISABus *pnv_chip_power10_isa_create(PnvChip *chip, Error **errp) { Pnv10Chip *chip10 = PNV10_CHIP(chip); - qemu_irq irq = qdev_get_gpio_in(DEVICE(&chip10->psi), PSIHB9_IRQ_LPCHC); + qemu_irq irq; + + irq = qdev_get_gpio_in(DEVICE(&chip10->psi), PSIHB9_IRQ_LPCHC); + qdev_connect_gpio_out_named(DEVICE(&chip10->lpc), "LPCHC", 0, irq); + + irq = qdev_get_gpio_in(DEVICE(&chip10->psi), PSIHB9_IRQ_LPC_SIRQ0); + qdev_connect_gpio_out_named(DEVICE(&chip10->lpc), "SERIRQ", 0, irq); + irq = qdev_get_gpio_in(DEVICE(&chip10->psi), PSIHB9_IRQ_LPC_SIRQ1); + qdev_connect_gpio_out_named(DEVICE(&chip10->lpc), "SERIRQ", 1, irq); + irq = qdev_get_gpio_in(DEVICE(&chip10->psi), PSIHB9_IRQ_LPC_SIRQ2); + qdev_connect_gpio_out_named(DEVICE(&chip10->lpc), "SERIRQ", 2, irq); + irq = qdev_get_gpio_in(DEVICE(&chip10->psi), PSIHB9_IRQ_LPC_SIRQ3); + qdev_connect_gpio_out_named(DEVICE(&chip10->lpc), "SERIRQ", 3, irq); - qdev_connect_gpio_out(DEVICE(&chip10->lpc), 0, irq); return pnv_lpc_isa_create(&chip10->lpc, false, errp); } diff --git a/hw/ppc/pnv_lpc.c b/hw/ppc/pnv_lpc.c index 7d26b29487..0f14e180af 100644 --- a/hw/ppc/pnv_lpc.c +++ b/hw/ppc/pnv_lpc.c @@ -64,6 +64,7 @@ enum { #define LPC_HC_IRQSER_START_4CLK 0x00000000 #define LPC_HC_IRQSER_START_6CLK 0x01000000 #define LPC_HC_IRQSER_START_8CLK 0x02000000 +#define LPC_HC_IRQSER_AUTO_CLEAR 0x00800000 #define LPC_HC_IRQMASK 0x34 /* same bit defs as LPC_HC_IRQSTAT */ #define LPC_HC_IRQSTAT 0x38 #define LPC_HC_IRQ_SERIRQ0 0x80000000 /* all bits down to ... */ @@ -420,32 +421,90 @@ static const MemoryRegionOps pnv_lpc_mmio_ops = { .endianness = DEVICE_BIG_ENDIAN, }; -static void pnv_lpc_eval_irqs(PnvLpcController *lpc) +/* Program the POWER9 LPC irq to PSI serirq routing table */ +static void pnv_lpc_eval_serirq_routes(PnvLpcController *lpc) { - bool lpc_to_opb_irq = false; + int irq; - /* Update LPC controller to OPB line */ - if (lpc->lpc_hc_irqser_ctrl & LPC_HC_IRQSER_EN) { - uint32_t irqs; + if (!lpc->psi_has_serirq) { + if ((lpc->opb_irq_route0 & PPC_BITMASK(8, 13)) || + (lpc->opb_irq_route1 & PPC_BITMASK(4, 31))) { + qemu_log_mask(LOG_GUEST_ERROR, + "OPB: setting serirq routing on POWER8 system, ignoring.\n"); + } + return; + } - irqs = lpc->lpc_hc_irqstat & lpc->lpc_hc_irqmask; - lpc_to_opb_irq = (irqs != 0); + for (irq = 0; irq <= 13; irq++) { + int serirq = (lpc->opb_irq_route1 >> (31 - 5 - (irq * 2))) & 0x3; + lpc->irq_to_serirq_route[irq] = serirq; } - /* We don't honor the polarity register, it's pointless and unused - * anyway - */ - if (lpc_to_opb_irq) { - lpc->opb_irq_input |= OPB_MASTER_IRQ_LPC; - } else { - lpc->opb_irq_input &= ~OPB_MASTER_IRQ_LPC; + for (irq = 14; irq < ISA_NUM_IRQS; irq++) { + int serirq = (lpc->opb_irq_route0 >> (31 - 9 - (irq * 2))) & 0x3; + lpc->irq_to_serirq_route[irq] = serirq; + } +} + +static void pnv_lpc_eval_irqs(PnvLpcController *lpc) +{ + uint32_t active_irqs = 0; + + if (lpc->lpc_hc_irqstat & PPC_BITMASK32(16, 31)) { + qemu_log_mask(LOG_UNIMP, "LPC HC Unimplemented irqs in IRQSTAT: " + "0x%08"PRIx32"\n", lpc->lpc_hc_irqstat); } - /* Update OPB internal latch */ - lpc->opb_irq_stat |= lpc->opb_irq_input & lpc->opb_irq_mask; + if (lpc->lpc_hc_irqser_ctrl & LPC_HC_IRQSER_EN) { + active_irqs = lpc->lpc_hc_irqstat & lpc->lpc_hc_irqmask; + } /* Reflect the interrupt */ - qemu_set_irq(lpc->psi_irq, lpc->opb_irq_stat != 0); + if (!lpc->psi_has_serirq) { + /* + * POWER8 ORs all irqs together (also with LPCHC internal interrupt + * sources) and outputs a single line that raises the PSI LPCHC irq + * which then latches an OPB IRQ status register that sends the irq + * to PSI. + * + * We don't honor the polarity register, it's pointless and unused + * anyway + */ + if (active_irqs) { + lpc->opb_irq_input |= OPB_MASTER_IRQ_LPC; + } else { + lpc->opb_irq_input &= ~OPB_MASTER_IRQ_LPC; + } + + /* Update OPB internal latch */ + lpc->opb_irq_stat |= lpc->opb_irq_input & lpc->opb_irq_mask; + + qemu_set_irq(lpc->psi_irq_lpchc, lpc->opb_irq_stat != 0); + } else { + /* + * POWER9 and POWER10 have routing fields in OPB master registers that + * send LPC irqs to 4 output lines that raise the PSI SERIRQ irqs. + * These don't appear to get latched into an OPB register like the + * LPCHC irqs. + * + * POWER9 LPC controller internal irqs still go via the OPB + * and LPCHC PSI irqs like P8, but we have no such internal sources + * modelled yet. + */ + bool serirq_out[4] = { false, false, false, false }; + int irq; + + for (irq = 0; irq < ISA_NUM_IRQS; irq++) { + if (active_irqs & (LPC_HC_IRQ_SERIRQ0 >> irq)) { + serirq_out[lpc->irq_to_serirq_route[irq]] = true; + } + } + + qemu_set_irq(lpc->psi_irq_serirq[0], serirq_out[0]); + qemu_set_irq(lpc->psi_irq_serirq[1], serirq_out[1]); + qemu_set_irq(lpc->psi_irq_serirq[2], serirq_out[2]); + qemu_set_irq(lpc->psi_irq_serirq[3], serirq_out[3]); + } } static uint64_t lpc_hc_read(void *opaque, hwaddr addr, unsigned size) @@ -543,10 +602,10 @@ static uint64_t opb_master_read(void *opaque, hwaddr addr, unsigned size) uint64_t val = 0xfffffffffffffffful; switch (addr) { - case OPB_MASTER_LS_ROUTE0: /* TODO */ + case OPB_MASTER_LS_ROUTE0: val = lpc->opb_irq_route0; break; - case OPB_MASTER_LS_ROUTE1: /* TODO */ + case OPB_MASTER_LS_ROUTE1: val = lpc->opb_irq_route1; break; case OPB_MASTER_LS_IRQ_STAT: @@ -575,11 +634,15 @@ static void opb_master_write(void *opaque, hwaddr addr, PnvLpcController *lpc = opaque; switch (addr) { - case OPB_MASTER_LS_ROUTE0: /* TODO */ + case OPB_MASTER_LS_ROUTE0: lpc->opb_irq_route0 = val; + pnv_lpc_eval_serirq_routes(lpc); + pnv_lpc_eval_irqs(lpc); break; - case OPB_MASTER_LS_ROUTE1: /* TODO */ + case OPB_MASTER_LS_ROUTE1: lpc->opb_irq_route1 = val; + pnv_lpc_eval_serirq_routes(lpc); + pnv_lpc_eval_irqs(lpc); break; case OPB_MASTER_LS_IRQ_STAT: lpc->opb_irq_stat &= ~val; @@ -664,6 +727,8 @@ static void pnv_lpc_power9_realize(DeviceState *dev, Error **errp) PnvLpcClass *plc = PNV_LPC_GET_CLASS(dev); Error *local_err = NULL; + object_property_set_bool(OBJECT(lpc), "psi-serirq", true, &error_abort); + plc->parent_realize(dev, &local_err); if (local_err) { error_propagate(errp, local_err); @@ -673,6 +738,9 @@ static void pnv_lpc_power9_realize(DeviceState *dev, Error **errp) /* P9 uses a MMIO region */ memory_region_init_io(&lpc->xscom_regs, OBJECT(lpc), &pnv_lpc_mmio_ops, lpc, "lpcm", PNV9_LPCM_SIZE); + + /* P9 LPC routes ISA irqs to 4 PSI SERIRQ lines */ + qdev_init_gpio_out_named(dev, lpc->psi_irq_serirq, "SERIRQ", 4); } static void pnv_lpc_power9_class_init(ObjectClass *klass, void *data) @@ -751,13 +819,19 @@ static void pnv_lpc_realize(DeviceState *dev, Error **errp) memory_region_add_subregion(&lpc->opb_mr, LPC_HC_REGS_OPB_ADDR, &lpc->lpc_hc_regs); - qdev_init_gpio_out(dev, &lpc->psi_irq, 1); + qdev_init_gpio_out_named(dev, &lpc->psi_irq_lpchc, "LPCHC", 1); } +static Property pnv_lpc_properties[] = { + DEFINE_PROP_BOOL("psi-serirq", PnvLpcController, psi_has_serirq, false), + DEFINE_PROP_END_OF_LIST(), +}; + static void pnv_lpc_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); + device_class_set_props(dc, pnv_lpc_properties); dc->realize = pnv_lpc_realize; dc->desc = "PowerNV LPC Controller"; dc->user_creatable = false; @@ -803,7 +877,7 @@ static void pnv_lpc_isa_irq_handler_cpld(void *opaque, int n, int level) } if (pnv->cpld_irqstate != old_state) { - qemu_set_irq(lpc->psi_irq, pnv->cpld_irqstate != 0); + qemu_set_irq(lpc->psi_irq_lpchc, pnv->cpld_irqstate != 0); } } @@ -824,6 +898,13 @@ static void pnv_lpc_isa_irq_handler(void *opaque, int n, int level) pnv_lpc_eval_irqs(lpc); } else { lpc->lpc_hc_irq_inputs &= ~irq_bit; + + /* POWER9 adds an auto-clear mode that clears IRQSTAT bits on EOI */ + if (lpc->psi_has_serirq && + (lpc->lpc_hc_irqser_ctrl & LPC_HC_IRQSER_AUTO_CLEAR)) { + lpc->lpc_hc_irqstat &= ~irq_bit; + pnv_lpc_eval_irqs(lpc); + } } } @@ -854,6 +935,7 @@ ISABus *pnv_lpc_isa_create(PnvLpcController *lpc, bool use_cpld, Error **errp) handler = pnv_lpc_isa_irq_handler; } + /* POWER has a 17th irq, QEMU only implements the 16 regular device irqs */ irqs = qemu_allocate_irqs(handler, lpc, ISA_NUM_IRQS); isa_bus_register_input_irqs(isa_bus, irqs); diff --git a/include/hw/ppc/pnv_lpc.h b/include/hw/ppc/pnv_lpc.h index 97c6872c3f..e0fd5e4130 100644 --- a/include/hw/ppc/pnv_lpc.h +++ b/include/hw/ppc/pnv_lpc.h @@ -23,6 +23,7 @@ #include "exec/memory.h" #include "hw/ppc/pnv.h" #include "hw/qdev-core.h" +#include "hw/isa/isa.h" /* For ISA_NUM_IRQS */ #define TYPE_PNV_LPC "pnv-lpc" typedef struct PnvLpcClass PnvLpcClass; @@ -87,8 +88,19 @@ struct PnvLpcController { /* XSCOM registers */ MemoryRegion xscom_regs; + /* + * In P8, ISA irqs are combined with internal sources to drive the + * LPCHC interrupt output. P9 ISA irqs raise one of 4 lines that + * drive PSI SERIRQ irqs, routing according to OPB routing registers. + */ + bool psi_has_serirq; + /* PSI to generate interrupts */ - qemu_irq psi_irq; + qemu_irq psi_irq_lpchc; + + /* P9 serirq lines and irq routing table */ + qemu_irq psi_irq_serirq[4]; + int irq_to_serirq_route[ISA_NUM_IRQS]; }; struct PnvLpcClass {