ppc/85xx: Add tracking of TLB CAM usage

We need to track which TLB CAM entries are used to allow us to
"dynamically" allocate entries later in the code.  For example the SPD
DDR code today hard codes which TLB entries it uses.  We can now make
that pick entries that are free.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

diff --git a/cpu/mpc85xx/cpu_init.c b/cpu/mpc85xx/cpu_init.c
index 16ce82c995c9210c32342f029472924e14c6df98..e0126d331af8f93ba1801401728a72fa7bcd2e87 100644 (file)
--- a/cpu/mpc85xx/cpu_init.c
+++ b/cpu/mpc85xx/cpu_init.c
@@ -246,6 +246,7 @@ void cpu_init_f (void)
 #ifdef CONFIG_FSL_CORENET
        corenet_tb_init();
 #endif
+       init_used_tlb_cams();
 }
 
 

diff --git a/cpu/mpc85xx/tlb.c b/cpu/mpc85xx/tlb.c
index ea5deb2971fcdf158e9bab50d976184d0f10d5ec..234fdaa60aa3d0ebbeb2677c46189deb32321022 100644 (file)
--- a/cpu/mpc85xx/tlb.c
+++ b/cpu/mpc85xx/tlb.c
@@ -56,12 +56,74 @@ void init_tlbs(void)
 }
 
 #ifndef CONFIG_NAND_SPL
+static inline void use_tlb_cam(u8 idx)
+{
+       int i = idx / 32;
+       int bit = idx % 32;
+
+       gd->used_tlb_cams[i] |= (1 << bit);
+}
+
+static inline void free_tlb_cam(u8 idx)
+{
+       int i = idx / 32;
+       int bit = idx % 32;
+
+       gd->used_tlb_cams[i] &= ~(1 << bit);
+}
+
+void init_used_tlb_cams(void)
+{
+       int i;
+       unsigned int num_cam = mfspr(SPRN_TLB1CFG) & 0xfff;
+
+       for (i = 0; i < ((CONFIG_SYS_NUM_TLBCAMS+31)/32); i++)
+               gd->used_tlb_cams[i] = 0;
+
+       /* walk all the entries */
+       for (i = 0; i < num_cam; i++) {
+               u32 _mas1;
+
+               mtspr(MAS0, FSL_BOOKE_MAS0(1, i, 0));
+
+               asm volatile("tlbre;isync");
+               _mas1 = mfspr(MAS1);
+
+               /* if the entry isn't valid skip it */
+               if ((_mas1 & MAS1_VALID))
+                       use_tlb_cam(i);
+       }
+}
+
+int find_free_tlbcam(void)
+{
+       int i;
+       u32 idx;
+
+       for (i = 0; i < ((CONFIG_SYS_NUM_TLBCAMS+31)/32); i++) {
+               idx = ffz(gd->used_tlb_cams[i]);
+
+               if (idx != 32)
+                       break;
+       }
+
+       idx += i * 32;
+
+       if (idx >= CONFIG_SYS_NUM_TLBCAMS)
+               return -1;
+
+       return idx;
+}
+
 void set_tlb(u8 tlb, u32 epn, u64 rpn,
             u8 perms, u8 wimge,
             u8 ts, u8 esel, u8 tsize, u8 iprot)
 {
        u32 _mas0, _mas1, _mas2, _mas3, _mas7;
 
+       if (tlb == 1)
+               use_tlb_cam(esel);
+
        _mas0 = FSL_BOOKE_MAS0(tlb, esel, 0);
        _mas1 = FSL_BOOKE_MAS1(1, iprot, 0, ts, tsize);
        _mas2 = FSL_BOOKE_MAS2(epn, wimge);
@@ -80,6 +142,8 @@ void disable_tlb(u8 esel)
 {
        u32 _mas0, _mas1, _mas2, _mas3, _mas7;
 
+       free_tlb_cam(esel);
+
        _mas0 = FSL_BOOKE_MAS0(1, esel, 0);
        _mas1 = 0;
        _mas2 = 0;

diff --git a/include/asm-ppc/config.h b/include/asm-ppc/config.h
index d5f82b44f3890ec03562a2ce62030a4e8f5771f5..796707eaf749592618c7d3d4fd344b97d2689274 100644 (file)
--- a/include/asm-ppc/config.h
+++ b/include/asm-ppc/config.h
@@ -63,6 +63,13 @@
 #define CONFIG_TSECV2
 #endif
 
+/* Number of TLB CAM entries we have on FSL Book-E chips */
+#if defined(CONFIG_E500MC)
+#define CONFIG_SYS_NUM_TLBCAMS 64
+#elif defined(CONFIG_E500)
+#define CONFIG_SYS_NUM_TLBCAMS 16
+#endif
+
 /* Relocation to SDRAM works on all PPC boards */
 #define CONFIG_RELOC_FIXUP_WORKS
 

diff --git a/include/asm-ppc/global_data.h b/include/asm-ppc/global_data.h
index 55e7e2066d8e69cce2b082ab71cc50b48c8586e8..3f119187464fc0696596c9022cfd46c0d81654ea 100644 (file)
--- a/include/asm-ppc/global_data.h
+++ b/include/asm-ppc/global_data.h
@@ -107,6 +107,9 @@ typedef     struct  global_data {
 #if defined(CONFIG_FSL_LAW)
        u32 used_laws;
 #endif
+#if defined(CONFIG_E500)
+       u32 used_tlb_cams[(CONFIG_SYS_NUM_TLBCAMS+31)/32];
+#endif
 #if defined(CONFIG_MPC5xxx)
        unsigned long   ipb_clk;
        unsigned long   pci_clk;

diff --git a/include/asm-ppc/mmu.h b/include/asm-ppc/mmu.h
index ec22a5058e1c0b2b829284246c8cf7bcec374b76..fd1024947d94e58e3725f4505198a142fd357e3f 100644 (file)
--- a/include/asm-ppc/mmu.h
+++ b/include/asm-ppc/mmu.h
@@ -479,6 +479,8 @@ extern void disable_tlb(u8 esel);
 extern void invalidate_tlb(u8 tlb);
 extern void init_tlbs(void);
 extern int find_tlb_idx(void *addr, u8 tlbsel);
+extern void init_used_tlb_cams(void);
+extern int find_free_tlbcam(void);
 
 extern unsigned int setup_ddr_tlbs(unsigned int memsize_in_meg);