Re: [PATCH] powerpc/44x: Support OCM(On Chip Memory) for APM821xx SoC and Bluestone board
From: Josh Boyer <hidden>
Date: 2012-06-14 17:47:29
Also in:
linuxppc-dev, lkml
On Sun, May 6, 2012 at 11:52 PM, Vinh Nguyen Huu Tuong [off-list ref] wrote:
This patch consists of: - Add driver for OCM component - Export OCM Information at /sys/class/ocm/ocminfo
Again, apologies for the delay. Aside from the incorrect sysfs usage I pointed out in my other reply, I have just a few comments/questions below.
quoted hunk ↗ jump to hunk
diff --git a/arch/powerpc/boot/dts/bluestone.dts b/arch/powerpc/boot/dts/bluestone.dts index 7bda373..2687c11 100644 --- a/arch/powerpc/boot/dts/bluestone.dts +++ b/arch/powerpc/boot/dts/bluestone.dts@@ -107,6 +107,14 @@interrupt-parent = <&UIC0>; }; + OCM1: ocm@400040000 { + compatible = "ibm,ocm"; + status = "ok"; + cell-index = <1>; + /* configured in U-Boot */ + reg = <4 0x00040000 0x8000>; /* 32K */ + }; + SDR0: sdr { compatible = "ibm,sdr-apm821xx"; dcr-reg = <0x00e 0x002>;diff --git a/arch/powerpc/include/asm/ppc4xx_ocm.h b/arch/powerpc/include/asm/ppc4xx_ocm.h new file mode 100644 index 0000000..ff7f386 --- /dev/null +++ b/arch/powerpc/include/asm/ppc4xx_ocm.h@@ -0,0 +1,47 @@ +/* + * PowerPC 4xx OCM memory allocation support + * + * (C) Copyright 2009, Applied Micro Circuits Corporation + * Victor Gallardo (vgallardo@amcc.com) + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#ifndef __ASM_POWERPC_PPC4xx_OCM_H__ +#define __ASM_POWERPC_PPC4xx_OCM_H__ + +#include <linux/types.h> + +#define OCM_NON_CACHED 0 +#define OCM_CACHED 1 + +#if defined(CONFIG_PPC4xx_OCM) + +void *ocm_alloc(phys_addr_t *phys, int size, int align, + int flags, const char *owner); +void ocm_free(const void *virt); + +#else + +#define ocm_alloc(phys, size, align, flags, owner) NULL +#define ocm_free(addr) ((void)0) + +#endif /* CONFIG_PPC4xx_OCM */ + +#endif /* __ASM_POWERPC_PPC4xx_OCM_H__ */
I don't see any users of this header included in the patch. I'm going to guess that follow-on drivers/users are queued once this is in the tree? Also, you might want to name these 'ppc4xx_ocm_alloc' or similar. The concept of OCM isn't limited to ppc4xx or even SoCs, so just using 'ocm' in the global kernel namespace might not be great.
quoted hunk ↗ jump to hunk
diff --git a/arch/powerpc/sysdev/ppc4xx_ocm.c b/arch/powerpc/sysdev/ppc4xx_ocm.c new file mode 100644 index 0000000..ba3e450 --- /dev/null +++ b/arch/powerpc/sysdev/ppc4xx_ocm.c@@ -0,0 +1,420 @@ +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/proc_fs.h>
Why do you need proc_fs.h?
+#include <linux/seq_file.h>
+#include <linux/spinlock.h>
+#include <linux/dma-mapping.h>
+#include <linux/list.h>
+#include <asm/uaccess.h>
+#include <asm/prom.h>
+#include <asm/dcr.h>
+#include <asm/rheap.h>
+#include <asm/mmu.h>
+#include <asm/ppc4xx_ocm.h>
+#include <linux/export.h>
+
+#define OCM_DISABLED 0
+#define OCM_ENABLED 1
+
+struct ocm_block {
+ struct list_head list;
+ void __iomem *addr;
+ int size;
+ const char *owner;
+};
+
+/* non-cached or cached region */
+struct ocm_region {
+ phys_addr_t phys;
+ void __iomem *virt;
+
+ int memtotal;
+ int memfree;
+
+ rh_info_t *rh;
+ struct list_head list;
+};There's some interesting whitespace usage in these struct definitions. josh