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Fix TQM8560 DDR boot issue

PATCH New Becky Bruce 3 participants 7 messages Jul 18, 2011 – Jul 25, 2011 PowerPC

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#0 lore raw

v2 cover Fix TQM8560 DDR boot issue

Series to fix the TQM85xx issue reported by Wolfgang.... the problem turned out to be that those boards use get_ram_size(), which requires that a TLB entry be set up for the DDR region. My earlier patches changed the way this was done and broke this.

I've created a new function, clear_ddr_tlbs(), so that there is now a setup_ddr_tlbs() and a matching clear_ddr_tlbs() that boards can use if they need to temporarily set up a TLB entry for this purpose. The tqm85xx ddr init code now uses this and the board is able to boot.

NOTE: There was another patch in this series that changed some include logic in the TQM85xx.h header file. I have dropped that patch as it was screwed up and not needed.

Cheers,
Becky

 arch/powerpc/cpu/mpc85xx/cpu.c |   14 +++-----------
 arch/powerpc/cpu/mpc85xx/tlb.c |   29 +++++++++++++++++++++++++++++
 arch/powerpc/include/asm/mmu.h |    1 +
 board/tqc/tqm85xx/sdram.c      |    7 +++++++
 include/configs/TQM85xx.h      |    6 ++++++
 5 files changed, 46 insertions(+), 11 deletions(-)
#1 lore raw

PATCH v2 1/2 powerpc/mpc85xx: Add clear_ddr_tlbs function

This is useful when we just want to wipe out the TLBs. There's currently a function that resets the ddr tlbs to a different value; it is changed to utilize this function. The new function can be used in conjunction with setup_ddr_tlbs() for a board to temporarily map/unmap the DDR address range as needed.

---
 arch/powerpc/cpu/mpc85xx/cpu.c |   14 +++-----------
 arch/powerpc/cpu/mpc85xx/tlb.c |   29 +++++++++++++++++++++++++++++
 arch/powerpc/include/asm/mmu.h |    1 +
 3 files changed, 33 insertions(+), 11 deletions(-)
arch/powerpc/cpu/mpc85xx/cpu.c +3 -11
index 53f0887..ce59c25 100644
@@ -374,6 +374,8 @@ void read_tlbcam_entry(int idx, u32 *valid, u32 *tsize, unsigned long *epn,
 unsigned int
 	setup_ddr_tlbs_phys(phys_addr_t p_addr, unsigned int memsize_in_meg);
 
+void clear_ddr_tlbs_phys(phys_addr_t p_addr, unsigned int memsize_in_meg);
+
 static void dump_spd_ddr_reg(void)
 {
 	int i, j, k, m;
@@ -460,19 +462,9 @@ static int reset_tlb(phys_addr_t p_addr, u32 size, phys_addr_t *phys_offset)
 	u32 vstart = CONFIG_SYS_DDR_SDRAM_BASE;
 	unsigned long epn;
 	u32 tsize, valid, ptr;
-	phys_addr_t rpn = 0;
 	int ddr_esel;
 
-	ptr = vstart;
-
-	while (ptr < (vstart + size)) {
-		ddr_esel = find_tlb_idx((void *)ptr, 1);
-		if (ddr_esel != -1) {
-			read_tlbcam_entry(ddr_esel, &valid, &tsize, &epn, &rpn);
-			disable_tlb(ddr_esel);
-		}
-		ptr += TSIZE_TO_BYTES(tsize);
-	}
+	clear_ddr_tlbs_phys(p_addr, size>>20);
 
 	/* Setup new tlb to cover the physical address */
 	setup_ddr_tlbs_phys(p_addr, size>>20);
arch/powerpc/cpu/mpc85xx/tlb.c +29 -0
index 295f175..01a3561 100644
@@ -300,4 +300,33 @@ unsigned int setup_ddr_tlbs(unsigned int memsize_in_meg)
 	return
 		setup_ddr_tlbs_phys(CONFIG_SYS_DDR_SDRAM_BASE, memsize_in_meg);
 }
+
+/* Invalidate the DDR TLBs for the requested size */
+void clear_ddr_tlbs_phys(phys_addr_t p_addr, unsigned int memsize_in_meg)
+{
+	u32 vstart = CONFIG_SYS_DDR_SDRAM_BASE;
+	unsigned long epn;
+	u32 tsize, valid, ptr;
+	phys_addr_t rpn = 0;
+	int ddr_esel;
+	u64 memsize = (u64)memsize_in_meg << 20;
+
+	ptr = vstart;
+
+	while (ptr < (vstart + memsize)) {
+		ddr_esel = find_tlb_idx((void *)ptr, 1);
+		if (ddr_esel != -1) {
+			read_tlbcam_entry(ddr_esel, &valid, &tsize, &epn, &rpn);
+			disable_tlb(ddr_esel);
+		}
+		ptr += TSIZE_TO_BYTES(tsize);
+	}
+}
+
+void clear_ddr_tlbs(unsigned int memsize_in_meg)
+{
+	clear_ddr_tlbs_phys(CONFIG_SYS_DDR_SDRAM_BASE, memsize_in_meg);
+}
+
+
 #endif /* !CONFIG_NAND_SPL */
arch/powerpc/include/asm/mmu.h +1 -0
index c01c85f..ef5076b 100644
@@ -489,6 +489,7 @@ extern int find_free_tlbcam(void);
 extern void print_tlbcam(void);
 
 extern unsigned int setup_ddr_tlbs(unsigned int memsize_in_meg);
+extern void clear_ddr_tlbs(unsigned int memsize_in_meg);
 
 extern void write_tlb(u32 _mas0, u32 _mas1, u32 _mas2, u32 _mas3, u32 _mas7);
 
Signature · 1 line
1.5.6.5
#2 lore raw

PATCH v2 2/2 board/tqm85xx: Create and tear down TLB for get_ram_size()

We need a TLB entry to call get_ram_size(); the common code doesn't create one until *after* fixed_sdram() has determined the size. So we set up tlbs for the max possible size and tear them down once we're done with get_ram_size(); the common 85xx code will then set up a final set of tlb entries for the *actual* detected size of ddr.

This prevents us from having TLB entries that are larger than DDR sitting around for very long, which is not a recommended scenario.

---
 board/tqc/tqm85xx/sdram.c |    7 +++++++
 include/configs/TQM85xx.h |    6 ++++++
 2 files changed, 13 insertions(+), 0 deletions(-)
board/tqc/tqm85xx/sdram.c +7 -0
index 39a9e21..baf073e 100644
@@ -363,6 +363,12 @@ static phys_size_t sdram_setup(int casl)
 	udelay (1000);
 #endif /* CONFIG_TQM8548 */
 
+	/*
+	 * get_ram_size() depends on having tlbs for the DDR, but they are
+	 * not yet setup because we don't know the size.  Set up a temp
+	 * mapping and delete it when done.
+	 */
+	setup_ddr_tlbs(CONFIG_SYS_DDR_EARLY_SIZE_MB);
 	for (i = 0; i < N_DDR_CS_CONF; i++) {
 		ddr->cs0_config = ddr_cs_conf[i].reg;
 
@@ -376,6 +382,7 @@ static phys_size_t sdram_setup(int casl)
 			break;
 		}
 	}
+	clear_ddr_tlbs(CONFIG_SYS_DDR_EARLY_SIZE_MB);
 
 #ifdef CONFIG_TQM8548
 	if (i < N_DDR_CS_CONF) {
include/configs/TQM85xx.h +6 -0
index 79a958d..b336723 100644
@@ -147,10 +147,16 @@
  * DDR Setup
  */
 #define CONFIG_SYS_DDR_SDRAM_BASE	0x00000000	/* DDR is system memory	*/
+
 #if defined(CONFIG_TQM_BIGFLASH) || \
 	(!defined(CONFIG_TQM8548_AG) && !defined(CONFIG_TQM8548_BE))
 #define CONFIG_SYS_PPC_DDR_WIMGE (MAS2_I | MAS2_G)
+#define CONFIG_SYS_DDR_EARLY_SIZE_MB	(512)
+#else
+#define CONFIG_SYS_PPC_DDR_WIMGE (0)
+#define CONFIG_SYS_DDR_EARLY_SIZE_MB	(2 * 1024)
 #endif
+
 #define CONFIG_SYS_SDRAM_BASE		CONFIG_SYS_DDR_SDRAM_BASE
 #ifdef CONFIG_TQM8548_AG
 #define CONFIG_VERY_BIG_RAM
Signature · 1 line
1.5.6.5
Applied
#3 lore raw

PATCH v2 2/2 board/tqm85xx: Create and tear down TLB for get_ram_size()

Quoted 11 lines · Becky Bruce

We need a TLB entry to call get_ram_size(); the common code doesn't create one until *after* fixed_sdram() has determined the size. So we set up tlbs for the max possible size and tear them down once we're done with get_ram_size(); the common 85xx code will then set up a final set of tlb entries for the *actual* detected size of ddr.

This prevents us from having TLB entries that are larger than DDR sitting around for very long, which is not a recommended scenario.

Quoted 5 lines

---

board/tqc/tqm85xx/sdram.c |    7 +++++++
include/configs/TQM85xx.h |    6 ++++++
2 files changed, 13 insertions(+), 0 deletions(-)

applied to 85xx

- k

#4 lore raw

PATCH v2 2/2 board/tqm85xx: Create and tear down TLB for get_ram_size()

In reply to Becky Bruce

Dear Becky Bruce,

Quoted 11 lines · In message <[email protected]> you wrote:

We need a TLB entry to call get_ram_size(); the common code doesn't create one until *after* fixed_sdram() has determined the size. So we set up tlbs for the max possible size and tear them down once we're done with get_ram_size(); the common 85xx code will then set up a final set of tlb entries for the *actual* detected size of ddr.

This prevents us from having TLB entries that are larger than DDR sitting around for very long, which is not a recommended scenario.

Quoted 5 lines
---
 board/tqc/tqm85xx/sdram.c |    7 +++++++
 include/configs/TQM85xx.h |    6 ++++++
 2 files changed, 13 insertions(+), 0 deletions(-)

Tested on TQM8555 / TQM8560.

Best regards,

Wolfgang Denk

Signature · 6 lines
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
If a man had a child who'd gone  anti-social,  killed  perhaps,  he'd
still tend to protect that child.
	-- McCoy, "The Ultimate Computer", stardate 4731.3
Applied
#5 lore raw

PATCH v2 1/2 powerpc/mpc85xx: Add clear_ddr_tlbs function

In reply to Becky Bruce
Quoted 6 lines · Becky Bruce

This is useful when we just want to wipe out the TLBs. There's currently a function that resets the ddr tlbs to a different value; it is changed to utilize this function. The new function can be used in conjunction with setup_ddr_tlbs() for a board to temporarily map/unmap the DDR address range as needed.

Quoted 6 lines

---

arch/powerpc/cpu/mpc85xx/cpu.c |   14 +++-----------
arch/powerpc/cpu/mpc85xx/tlb.c |   29 +++++++++++++++++++++++++++++
arch/powerpc/include/asm/mmu.h |    1 +
3 files changed, 33 insertions(+), 11 deletions(-)

applied to 85xx

- k

#6 lore raw

PATCH v2 1/2 powerpc/mpc85xx: Add clear_ddr_tlbs function

In reply to Becky Bruce

Dear Becky Bruce,

Quoted 6 lines · In message <[email protected]> you wrote:

This is useful when we just want to wipe out the TLBs. There's currently a function that resets the ddr tlbs to a different value; it is changed to utilize this function. The new function can be used in conjunction with setup_ddr_tlbs() for a board to temporarily map/unmap the DDR address range as needed.

Quoted 6 lines
---
 arch/powerpc/cpu/mpc85xx/cpu.c |   14 +++-----------
 arch/powerpc/cpu/mpc85xx/tlb.c |   29 +++++++++++++++++++++++++++++
 arch/powerpc/include/asm/mmu.h |    1 +
 3 files changed, 33 insertions(+), 11 deletions(-)

Tested on TQM8555 / TQM8560.

Best regards,

Wolfgang Denk

Signature · 6 lines
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
The use of COBOL cripples the mind; its teaching  should,  therefore,
be regarded as a criminal offence.
          -- Edsger W. Dijkstra, SIGPLAN Notices, Volume 17, Number 5