From mboxrd@z Thu Jan 1 00:00:00 1970 From: Philipp Zabel Subject: Re: [PATCH v8 2/6] misc: sram: implement reserved sram areas Date: Mon, 03 Mar 2014 12:29:47 +0100 Message-ID: <1393846187.3369.0.camel@paszta.hi.pengutronix.de> References: <21117503.1c6iOkvYSr@phil> <8769537.NUv9SMRkyo@phil> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <8769537.NUv9SMRkyo@phil> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Heiko =?ISO-8859-1?Q?St=FCbner?= Cc: "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , arm-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, Grant Likely , Rob Herring , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Greg Kroah-Hartman , Pawel Moll , Mark Rutland , Stephen Warren , Ian Campbell List-Id: devicetree@vger.kernel.org Hi Heiko, Am Dienstag, den 25.02.2014, 12:46 +0100 schrieb Heiko St=C3=BCbner: > This implements support for defining reserved areas as subnodes, > to keep the genpool from using these. >=20 > Suggested-by: Rob Herring > Signed-off-by: Heiko Stuebner > Tested-by: Ulrich Prinz Acked-by: Philipp Zabel > --- > drivers/misc/sram.c | 125 ++++++++++++++++++++++++++++++++++++++++++= +++++++--- > 1 file changed, 118 insertions(+), 7 deletions(-) >=20 > diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c > index afe66571..674b0cd 100644 > --- a/drivers/misc/sram.c > +++ b/drivers/misc/sram.c > @@ -24,6 +24,9 @@ > #include > #include > #include > +#include > +#include > +#include > #include > #include > #include > @@ -36,14 +39,35 @@ struct sram_dev { > struct clk *clk; > }; > =20 > +struct sram_reserve { > + struct list_head list; > + u32 start; > + u32 size; > +}; > + > +static int sram_reserve_cmp(void *priv, struct list_head *a, > + struct list_head *b) > +{ > + struct sram_reserve *ra =3D list_entry(a, struct sram_reserve, list= ); > + struct sram_reserve *rb =3D list_entry(b, struct sram_reserve, list= ); > + > + return ra->start - rb->start; > +} > + > static int sram_probe(struct platform_device *pdev) > { > void __iomem *virt_base; > struct sram_dev *sram; > struct resource *res; > - unsigned long size; > + struct device_node *np =3D pdev->dev.of_node, *child; > + unsigned long size, cur_start, cur_size; > + struct sram_reserve *rblocks, *block; > + struct list_head reserve_list; > + unsigned int nblocks; > int ret; > =20 > + INIT_LIST_HEAD(&reserve_list); > + > res =3D platform_get_resource(pdev, IORESOURCE_MEM, 0); > virt_base =3D devm_ioremap_resource(&pdev->dev, res); > if (IS_ERR(virt_base)) > @@ -65,19 +89,106 @@ static int sram_probe(struct platform_device *pd= ev) > if (!sram->pool) > return -ENOMEM; > =20 > - ret =3D gen_pool_add_virt(sram->pool, (unsigned long)virt_base, > - res->start, size, -1); > - if (ret < 0) { > - if (sram->clk) > - clk_disable_unprepare(sram->clk); > - return ret; > + /* > + * We need an additional block to mark the end of the memory region > + * after the reserved blocks from the dt are processed. > + */ > + nblocks =3D (np) ? of_get_available_child_count(np) + 1 : 1; > + rblocks =3D kmalloc((nblocks) * sizeof(*rblocks), GFP_KERNEL); > + if (!rblocks) { > + ret =3D -ENOMEM; > + goto err_alloc; > } > =20 > + block =3D &rblocks[0]; > + for_each_available_child_of_node(np, child) { > + struct resource child_res; > + > + ret =3D of_address_to_resource(child, 0, &child_res); > + if (ret < 0) { > + dev_err(&pdev->dev, > + "could not get address for node %s\n", > + child->full_name); > + goto err_chunks; > + } > + > + if (child_res.start < res->start || child_res.end > res->end) { > + dev_err(&pdev->dev, > + "reserved block %s outside the sram area\n", > + child->full_name); > + ret =3D -EINVAL; > + goto err_chunks; > + } > + > + block->start =3D child_res.start - res->start; > + block->size =3D resource_size(&child_res); > + list_add_tail(&block->list, &reserve_list); > + > + dev_dbg(&pdev->dev, "found reserved block 0x%x-0x%x\n", > + block->start, > + block->start + block->size); > + > + block++; > + } > + > + /* the last chunk marks the end of the region */ > + rblocks[nblocks - 1].start =3D size; > + rblocks[nblocks - 1].size =3D 0; > + list_add_tail(&rblocks[nblocks - 1].list, &reserve_list); > + > + list_sort(NULL, &reserve_list, sram_reserve_cmp); > + > + cur_start =3D 0; > + > + list_for_each_entry(block, &reserve_list, list) { > + /* can only happen if sections overlap */ > + if (block->start < cur_start) { > + dev_err(&pdev->dev, > + "block at 0x%x starts after current offset 0x%lx\n", > + block->start, cur_start); > + ret =3D -EINVAL; > + goto err_chunks; > + } > + > + /* current start is in a reserved block, so continue after it */ > + if (block->start =3D=3D cur_start) { > + cur_start =3D block->start + block->size; > + continue; > + } > + > + /* > + * allocate the space between the current starting > + * address and the following reserved block, or the > + * end of the region. > + */ > + cur_size =3D block->start - cur_start; > + > + dev_dbg(&pdev->dev, "adding chunk 0x%lx-0x%lx\n", > + cur_start, cur_start + cur_size); > + ret =3D gen_pool_add_virt(sram->pool, > + (unsigned long)virt_base + cur_start, > + res->start + cur_start, cur_size, -1); > + if (ret < 0) > + goto err_chunks; > + > + /* next allocation after this reserved block */ > + cur_start =3D block->start + block->size; > + } > + > + kfree(rblocks); > + > platform_set_drvdata(pdev, sram); > =20 > dev_dbg(&pdev->dev, "SRAM pool: %ld KiB @ 0x%p\n", size / 1024, vir= t_base); > =20 > return 0; > + > +err_chunks: > + kfree(rblocks); > +err_alloc: > + if (sram->clk) > + clk_disable_unprepare(sram->clk); > + return ret; > } > =20 > static int sram_remove(struct platform_device *pdev) regards Philipp -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html