From mboxrd@z Thu Jan 1 00:00:00 1970 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 399E7C433F5 for ; Wed, 13 Apr 2022 20:25:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:References: List-Owner; bh=AE4hYKLHp/AAAHvUiIBEsS796Goq/a7Q5JSLYg+eZfE=; b=uXq/m8v6OXmuL1 a17c13hcQvDlVmwsnV6UxxnKUYa6zqksCKBSQ6VC/y4EMwajZ2Sjg4pkg8m44BBygFhBs0q/7savn XpPetm5BWV/sHgFfWljcALvS4kgr86fPvS8AJ82UzNC7unXzj+gbbOI0hzSPMIQ431jpxmcsg1S6C gx3lW937zldowQ1EeSTp1L0aPwVHT3mNVC/MEfmz26UzA/LfgsYNneUti9O5Lk6wKAk5sez8yWEom Xo+ab62WsuOvCyeL6fKmNSy0DWlDYQGM6AzJYYEwkHzn7mP43JNUS+UKbx2+o3Rg/gtOIdedvnVkY ATojxygpPHRD2h8krXpw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nejXb-002e9I-J7; Wed, 13 Apr 2022 20:24:39 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nejXY-002e8q-Dy for linux-arm-kernel@lists.infradead.org; Wed, 13 Apr 2022 20:24:38 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4FD1661DC8; Wed, 13 Apr 2022 20:24:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74DC9C385A3; Wed, 13 Apr 2022 20:24:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1649881474; bh=2RUFHWOD1DBlUTn0rn61mqQySRcJDmALxwyHtmWQLn4=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=aPH+4hetSldTnCtYHjSjHZlS36hTdhia7zn2zq5SX+9G3sxebtuIGhxzH4OX+gewX PwKr+qSWt43HeN9yS2K6MnnPAPG8eQ8M7OHsb0I5BTWocd687ok+ILwuCKlqU/9+HS 2jifTC9ITN1nypIBnd1AnFFy6wzKK6342rYpa8cEAusITN6nQFyFfbQJAhrikjtyLz /+ghhMdq4TNhVltD1YGkZ6B79kRNI6KvcS7IVuRLq8QAagLI0/fjR7YjpmNlp5GxuD j/XV3OtY6eRyeRVPZRo5ShiVXbh48oY1pTyGusvti9IMmzdPJW+wjHfKwWzdtnuDAg lRhsVVhxYZ2XQ== Date: Wed, 13 Apr 2022 15:24:33 -0500 From: Bjorn Helgaas To: Pali =?iso-8859-1?Q?Roh=E1r?= Cc: Lorenzo Pieralisi , Bjorn Helgaas , Rob Herring , Andrew Lunn , Thomas Petazzoni , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Marek =?iso-8859-1?Q?Beh=FAn?= , Russell King , linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 3/4] PCI: Add function for parsing 'slot-power-limit-milliwatt' DT property Message-ID: <20220413202433.GA688099@bhelgaas> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220412094946.27069-4-pali@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220413_132436_590154_BA3A0C1C X-CRM114-Status: GOOD ( 26.72 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Apr 12, 2022 at 11:49:45AM +0200, Pali Roh=E1r wrote: > Add function of_pci_get_slot_power_limit(), which parses the > 'slot-power-limit-milliwatt' DT property, returning the value in > milliwatts and in format ready for the PCIe Slot Capabilities Register. > = > Signed-off-by: Pali Roh=E1r > Signed-off-by: Marek Beh=FAn > Reviewed-by: Rob Herring Looks good to me! Thank you! Reviewed-by: Bjorn Helgaas > --- > Changes in v4: > * Set 239 W when DT slot-power-limit-milliwatt is between 239 W and 250 W > * Fix returning power limit value > Changes in v3: > * Set 600 W when DT slot-power-limit-milliwatt > 600 W > Changes in v2: > * Added support for PCIe 6.0 slot power limit encodings > * Round down slot power limit value > --- > drivers/pci/of.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++ > drivers/pci/pci.h | 15 ++++++++++ > 2 files changed, 85 insertions(+) > = > diff --git a/drivers/pci/of.c b/drivers/pci/of.c > index cb2e8351c2cc..6c1b81304665 100644 > --- a/drivers/pci/of.c > +++ b/drivers/pci/of.c > @@ -633,3 +633,73 @@ int of_pci_get_max_link_speed(struct device_node *no= de) > return max_link_speed; > } > EXPORT_SYMBOL_GPL(of_pci_get_max_link_speed); > + > +/** > + * of_pci_get_slot_power_limit - Parses the "slot-power-limit-milliwatt" > + * property. > + * > + * @node: device tree node with the slot power limit information > + * @slot_power_limit_value: pointer where the value should be stored in = PCIe > + * Slot Capabilities Register format > + * @slot_power_limit_scale: pointer where the scale should be stored in = PCIe > + * Slot Capabilities Register format > + * > + * Returns the slot power limit in milliwatts and if @slot_power_limit_v= alue > + * and @slot_power_limit_scale pointers are non-NULL, fills in the value= and > + * scale in format used by PCIe Slot Capabilities Register. > + * > + * If the property is not found or is invalid, returns 0. > + */ > +u32 of_pci_get_slot_power_limit(struct device_node *node, > + u8 *slot_power_limit_value, > + u8 *slot_power_limit_scale) > +{ > + u32 slot_power_limit_mw; > + u8 value, scale; > + > + if (of_property_read_u32(node, "slot-power-limit-milliwatt", > + &slot_power_limit_mw)) > + slot_power_limit_mw =3D 0; > + > + /* Calculate Slot Power Limit Value and Slot Power Limit Scale */ > + if (slot_power_limit_mw =3D=3D 0) { > + value =3D 0x00; > + scale =3D 0; > + } else if (slot_power_limit_mw <=3D 255) { > + value =3D slot_power_limit_mw; > + scale =3D 3; > + } else if (slot_power_limit_mw <=3D 255*10) { > + value =3D slot_power_limit_mw / 10; > + scale =3D 2; > + slot_power_limit_mw =3D slot_power_limit_mw / 10 * 10; > + } else if (slot_power_limit_mw <=3D 255*100) { > + value =3D slot_power_limit_mw / 100; > + scale =3D 1; > + slot_power_limit_mw =3D slot_power_limit_mw / 100 * 100; > + } else if (slot_power_limit_mw <=3D 239*1000) { > + value =3D slot_power_limit_mw / 1000; > + scale =3D 0; > + slot_power_limit_mw =3D slot_power_limit_mw / 1000 * 1000; > + } else if (slot_power_limit_mw < 250*1000) { > + value =3D 0xEF; > + scale =3D 0; > + slot_power_limit_mw =3D 239*1000; > + } else if (slot_power_limit_mw <=3D 600*1000) { > + value =3D 0xF0 + (slot_power_limit_mw / 1000 - 250) / 25; > + scale =3D 0; > + slot_power_limit_mw =3D slot_power_limit_mw / (1000*25) * (1000*25); > + } else { > + value =3D 0xFE; > + scale =3D 0; > + slot_power_limit_mw =3D 600*1000; > + } > + > + if (slot_power_limit_value) > + *slot_power_limit_value =3D value; > + > + if (slot_power_limit_scale) > + *slot_power_limit_scale =3D scale; > + > + return slot_power_limit_mw; > +} > +EXPORT_SYMBOL_GPL(of_pci_get_slot_power_limit); > diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h > index 3d60cabde1a1..e10cdec6c56e 100644 > --- a/drivers/pci/pci.h > +++ b/drivers/pci/pci.h > @@ -627,6 +627,9 @@ struct device_node; > int of_pci_parse_bus_range(struct device_node *node, struct resource *re= s); > int of_get_pci_domain_nr(struct device_node *node); > int of_pci_get_max_link_speed(struct device_node *node); > +u32 of_pci_get_slot_power_limit(struct device_node *node, > + u8 *slot_power_limit_value, > + u8 *slot_power_limit_scale); > void pci_set_of_node(struct pci_dev *dev); > void pci_release_of_node(struct pci_dev *dev); > void pci_set_bus_of_node(struct pci_bus *bus); > @@ -653,6 +656,18 @@ of_pci_get_max_link_speed(struct device_node *node) > return -EINVAL; > } > = > +static inline u32 > +of_pci_get_slot_power_limit(struct device_node *node, > + u8 *slot_power_limit_value, > + u8 *slot_power_limit_scale) > +{ > + if (slot_power_limit_value) > + *slot_power_limit_value =3D 0; > + if (slot_power_limit_scale) > + *slot_power_limit_scale =3D 0; > + return 0; > +} > + > static inline void pci_set_of_node(struct pci_dev *dev) { } > static inline void pci_release_of_node(struct pci_dev *dev) { } > static inline void pci_set_bus_of_node(struct pci_bus *bus) { } > -- = > 2.20.1 > = > = > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel