[POWERPC] cpm: Describe multi-user ram in its own device node.

The way the current CPM binding describes available multi-user (a.k.a.
dual-ported) RAM doesn't work well when there are multiple free regions,
and it doesn't work at all if the region doesn't begin at the start of
the muram area (as the hardware needs to be programmed with offsets into
this area).  The latter situation can happen with SMC UARTs on CPM2, as its
parameter RAM is relocatable, u-boot puts it at zero, and the kernel doesn't
support moving it.

It is now described with a muram node, similar to QE.  The current CPM
binding is sufficiently recent (i.e. never appeared in an official release)
that compatibility with existing device trees is not an issue.

The code supporting the new binding is shared between cpm1 and cpm2, rather
than remain separated.  QE should be able to use this code as well, once
minor fixes are made to its device trees.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

3 files changed, 36 insertions, 0 deletions

diff --git a/include/asm-powerpc/commproc.h b/include/asm-powerpc/commproc.h
index 5dec32404fa2..0307c84a5c1d 100644
--- a/include/asm-powerpc/commproc.h
+++ b/include/asm-powerpc/commproc.h
@@ -19,6 +19,7 @@
 
 #include <asm/8xx_immap.h>
 #include <asm/ptrace.h>
+#include <asm/cpm.h>
 
 /* CPM Command register.
 */
@@ -54,6 +55,7 @@
 
 #define mk_cr_cmd(CH, CMD)      ((CMD << 8) | (CH << 4))
 
+#ifndef CONFIG_PPC_CPM_NEW_BINDING
 /* The dual ported RAM is multi-functional.  Some areas can be (and are
  * being) used for microcode.  There is an area that can only be used
  * as data ram for buffer descriptors, which is all we use right now.
@@ -62,17 +64,27 @@
 #define CPM_DATAONLY_BASE       ((uint)0x0800)
 #define CPM_DATAONLY_SIZE       ((uint)0x0700)
 #define CPM_DP_NOSPACE          ((uint)0x7fffffff)
+#endif
 
 /* Export the base address of the communication processor registers
  * and dual port ram.
  */
 extern cpm8xx_t __iomem *cpmp; /* Pointer to comm processor */
+
+#ifdef CONFIG_PPC_CPM_NEW_BINDING
+#define cpm_dpalloc cpm_muram_alloc
+#define cpm_dpfree cpm_muram_free
+#define cpm_dpram_addr cpm_muram_addr
+#define cpm_dpram_phys cpm_muram_dma
+#else
 extern unsigned long cpm_dpalloc(uint size, uint align);
 extern int cpm_dpfree(unsigned long offset);
 extern unsigned long cpm_dpalloc_fixed(unsigned long offset, uint size, uint align);
 extern void cpm_dpdump(void);
 extern void *cpm_dpram_addr(unsigned long offset);
 extern uint cpm_dpram_phys(u8* addr);
+#endif
+
 extern void cpm_setbrg(uint brg, uint rate);
 
 extern uint m8xx_cpm_hostalloc(uint size);
diff --git a/include/asm-powerpc/cpm.h b/include/asm-powerpc/cpm.h
new file mode 100644
index 000000000000..48df9f330e76
--- /dev/null
+++ b/include/asm-powerpc/cpm.h
@@ -0,0 +1,14 @@
+#ifndef __CPM_H
+#define __CPM_H
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+
+int cpm_muram_init(void);
+unsigned long cpm_muram_alloc(unsigned long size, unsigned long align);
+int cpm_muram_free(unsigned long offset);
+unsigned long cpm_muram_alloc_fixed(unsigned long offset, unsigned long size);
+void __iomem *cpm_muram_addr(unsigned long offset);
+dma_addr_t cpm_muram_dma(void __iomem *addr);
+
+#endif
diff --git a/include/asm-powerpc/cpm2.h b/include/asm-powerpc/cpm2.h
index d7b57ac55892..e698b1d09dcf 100644
--- a/include/asm-powerpc/cpm2.h
+++ b/include/asm-powerpc/cpm2.h
@@ -11,6 +11,7 @@
 #define __CPM2__
 
 #include <asm/immap_cpm2.h>
+#include <asm/cpm.h>
 
 /* CPM Command register.
 */
@@ -82,6 +83,7 @@
 #define mk_cr_cmd(PG, SBC, MCN, OP) \
         ((PG << 26) | (SBC << 21) | (MCN << 6) | OP)
 
+#ifndef CONFIG_PPC_CPM_NEW_BINDING
 /* Dual Port RAM addresses.  The first 16K is available for almost
  * any CPM use, so we put the BDs there.  The first 128 bytes are
  * used for SMC1 and SMC2 parameter RAM, so we start allocating
@@ -97,6 +99,7 @@
 #define CPM_DATAONLY_SIZE       ((uint)(16 * 1024) - CPM_DATAONLY_BASE)
 #define CPM_FCC_SPECIAL_BASE    ((uint)0x0000b000)
 #endif
+#endif
 
 /* The number of pages of host memory we allocate for CPM.  This is
  * done early in kernel initialization to get physically contiguous
@@ -109,11 +112,18 @@
  */
 extern cpm_cpm2_t __iomem *cpmp; /* Pointer to comm processor */
 
+#ifdef CONFIG_PPC_CPM_NEW_BINDING
+#define cpm_dpalloc cpm_muram_alloc
+#define cpm_dpfree cpm_muram_free
+#define cpm_dpram_addr cpm_muram_addr
+#else
 extern unsigned long cpm_dpalloc(uint size, uint align);
 extern int cpm_dpfree(unsigned long offset);
 extern unsigned long cpm_dpalloc_fixed(unsigned long offset, uint size, uint align);
 extern void cpm_dpdump(void);
 extern void *cpm_dpram_addr(unsigned long offset);
+#endif
+
 extern void cpm_setbrg(uint brg, uint rate);
 extern void cpm2_fastbrg(uint brg, uint rate, int div16);
 extern void cpm2_reset(void);